Glock 27 .40 Kaboom this weekend

[Rocky Patel]

Mr. Rocky Patel,

I will not venture a guess what caused your KB/

But will suggest the things I do.

Buy yourself a small desk reading light with a flex/adjustable neck, can get em at LOWES with em new type bulbs. About $20 !

Get a wire frame make-up mirrow 3X at the Dollar Store,($3 or $4), attach to the press so every time you place a bullet on a case you can look in the case. if you don't see powder at the right level DON'T place a bullet. Train yourself to look every time you pull the handle.

Buy youself a CHRONO, pay attention when at your press, wear safety glasses, run a ground wire from a mounting bolt on the press to an electrical ground or water pipe. Static Electricity can do strange things.

Be SAFE and careful, the fingers and eye ball you save may be yours,

Be very cautious where you get loading data and info, do your own research.

Re-loading is like a hobby in a hobby, don't do dumb sheit.

Perry

Thanks for the input Perry. Didn't think about the ground wire thing. Thats a good Idea. I've made probably 600 rounds since then and actually, now it is habit that look in the shell for the right level of powder before the bullet. I've caught zero double charges go by BUT have seen maybe 3-4 cases with no powder. Sometimes the lee disk gets stuck in place from the dumping powder from the last round and does not go back to the reset point. So when I pull the handle nothing comes out. There is also a different feeling in the handle( less resistance) when this happens. But a few times the looking caught the empty cases. As far as light goes I moved a lamp closer but I do want to get a small positionable light.

[98sr20ve]

I've caught zero double charges go by BUT have seen maybe 3-4 cases with no powder. Sometimes the lee disk gets stuck in place from the dumping powder from the last round and does not go back to the reset point. So when I pull the handle nothing comes out. There is also a different feeling in the handle( less resistance) when this happens. But a few times the looking caught the empty cases. As far as light goes I moved a lamp closer but I do want to get a small positionable light.

People love to bash Lee but you should not be having that issue. Find out why it's sticking. Perhaps you over tightened the two screws? Are you using a spring on the measure I assume. Is it a Pro Disc or the older aluminum one? I have never used the aluminum one. My Pro is perfect.

[Rocky Patel]

I've caught zero double charges go by BUT have seen maybe 3-4 cases with no powder. Sometimes the lee disk gets stuck in place from the dumping powder from the last round and does not go back to the reset point. So when I pull the handle nothing comes out. There is also a different feeling in the handle( less resistance) when this happens. But a few times the looking caught the empty cases. As far as light goes I moved a lamp closer but I do want to get a small positionable light.

People love to bash Lee but you should not be having that issue. Find out why it's sticking. Perhaps you over tightened the two screws? Are you using a spring on the measure I assume. Is it a Pro Disc or the older aluminum one? I have never used the aluminum one. My Pro is perfect.

Not bashing the lee. I like it for the money I spent on it. After getting all the good advise from you folks. I've successfully made almost 1000 rounds so far. I wish it was a little faster though. Not sure why it's sticking. I have to give it a little tap to spring it back to the reset point. The one I have is the non- pro model that came with my turret deluxe. Then I upgraded the hopper with the pro upgrade kit. Which consists of a swivel adapter and a round hopper. Still use the round disks..

[jdknotts1]

Did you ever go to Glock and ask them about the barrel?

[98sr20ve]

I've caught zero double charges go by BUT have seen maybe 3-4 cases with no powder. Sometimes the lee disk gets stuck in place from the dumping powder from the last round and does not go back to the reset point. So when I pull the handle nothing comes out. There is also a different feeling in the handle( less resistance) when this happens. But a few times the looking caught the empty cases. As far as light goes I moved a lamp closer but I do want to get a small positionable light.

People love to bash Lee but you should not be having that issue. Find out why it's sticking. Perhaps you over tightened the two screws? Are you using a spring on the measure I assume. Is it a Pro Disc or the older aluminum one? I have never used the aluminum one. My Pro is perfect.

Not bashing the lee. I like it for the money I spent on it. After getting all the good advise from you folks. I've successfully made almost 1000 rounds so far. I wish it was a little faster though. Not sure why it's sticking. I have to give it a little tap to spring it back to the reset point. The one I have is the non- pro model that came with my turret deluxe. Then I upgraded the hopper with the pro upgrade kit. Which consists of a swivel adapter and a round hopper. Still use the round disks..

I didn't think you were bashing. I would call Lee. It should not be sticking. Send it back and get another one. Ammo is too important to live with that. My Pro never sticks. I have owned several.

[redbulladdikt]

Sorry to hear about your Glock going to Handgun Heaven but very glad u lived to tell the tale! ( I suppose u got one helluva piece of wall art too!)

I am loading .40 cal exclusively and your tale is precisely why I am being cautious about my powder loads...fwiw this is what I am using for my setup--while I am a newb to loading my Dad has 20 years of experience and lent a hand in mocking up a consistent formula and confirming it....and for the 7-millionth time, seriously, invest in a Dillon! I have had mine less than 3 weeks and cranked out 2k loads and have 100% confidence in them all!

We are using Alliant Power Pistol...dropping 6.0 grains...once-fired factory brass (all through personal .40s no range-brass) loading 180grain Winchester FMJ and Rainier 180 plated semi-wads....using 1 1/2 Remington Small primers (its what's readily available locally)

Hope this helps and yet again thanks for sharing with us and glad u r OK--oh and enjoy the new toy (but try not to make it Ka-Boom too!)

[Rocky Patel]

Did you ever go to Glock and ask them about the barrel?

Not yet. I've been so busy. Haven't had a chance to get a hair cut. been meaning to for 3 weeks.. I will though..The Glock thing that is.

[noexcuses]

Sorry to hear about your Glock going to Handgun Heaven but very glad u lived to tell the tale! ( I suppose u got one helluva piece of wall art too!)

I am loading .40 cal exclusively and your tale is precisely why I am being cautious about my powder loads...fwiw this is what I am using for my setup--while I am a newb to loading my Dad has 20 years of experience and lent a hand in mocking up a consistent formula and confirming it....and for the 7-millionth time, seriously, invest in a Dillon! I have had mine less than 3 weeks and cranked out 2k loads and have 100% confidence in them all!

We are using Alliant Power Pistol...dropping 6.0 grains...once-fired factory brass (all through personal .40s no range-brass) loading 180grain Winchester FMJ and Rainier 180 plated semi-wads....using 1 1/2 Remington Small primers (its what's readily available locally)

Hope this helps and yet again thanks for sharing with us and glad u r OK--oh and enjoy the new toy (but try not to make it Ka-Boom too!)

just to give you a heads up Remington does not recomened the 1 1/2's for 40 S&W, they recomened you use the 5 1/2's.

[Edubya]

I like what Perrysho said about grounding the powder container but if that's not easily done, keep some anti static dryer sheets near by and wipe your container down ever so often. It really won't make that much difference but it might make that 0.1 (between 4.1 & 4.2) more consistent.

EW

[TonyT]

Rocky Patel,

Good to hear you were not injured. From your description I believe the only possible explanation is a double charge. I use a Dillon 550 and inspect each case for powder drop before proceedng to bullet seating. I gave up using Titegroup because it burns too hot and has too many fine particles. For light loads, ca 725 to 750 fps, I use WST whose light grey color is easilly seen in the case before bullet seating. For loads approaching full power I use WSF. Both WST and WSF meter with exceptional uniformity. Power Pistol is also a good choice for full power loads.

[fishpinoy27]

Crimp is not what is meant to hold a bullet in place. Try it again. Even with no crimp you should not be able to move the bullet by hand. Case tension holds the bullet in place on a pistol.

Also, The safest way to load on the LCT is in auto index mode. 1 case goes in and it doesn't come out till it's loaded and finished. Visually you will know if you have enough powder. A fixed disc can't not overcharge by much. It's just not going to happen. But it can throw light. But you would see it if it was really light. Weighting every 10 rounds gets old and messes up your rhythm. It's also a great way to get a squib. NEVER have more then one throw of powder out of the bench. If you do it can lead to a double.

Minor setback was not your problem. Your kidding yourself if you think that is what it was. It was a double charge or a MAJOR setback.

+1..

that's why I replaced my sizing die with the EGW "U" (undersize) Die...to increase the tension...remember .40 S&W cartridge are already high pressure and you compressed (setback) it a little more and it will jump the pressure sky high... I also change my powder from TG to N320... more softer loads...And I notice it, with the same power factor the n320 are softer than the TG.

[partyboy424]

Just going to put in two parts for those of us with Lee Auto Disk Dispensers. That dog tag chain that it uses is a truly terrible design, it can loosen causing erratic powder charges and get hung up and snap. Which will cause you to lose the locking ends which will lead to more loosening. IMHO it's dangerous to have on your setup. I really wish lee would let you custom setup your packages with the best of the best parts, I've added about $20 worth from their replacement parts catolog that have made it an excellent press and now I load 9, 40 and 45 with complete confidence.

To get rid of that chain and gain the ability to trust your powder drop, just buy these two parts.

midwayusa product/334897

midwayusa product/543877

When you buy the pro autodisk it actually comes with these pre installed and leaves the chain as the backup part (though you will never need it and it is not shown this way in the picture)

Kevin

[Yardbird]

Just going to put in two parts for those of us with Lee Auto Disk Dispensers. That dog tag chain that it uses is a truly terrible design, it can loosen causing erratic powder charges and get hung up and snap. Which will cause you to lose the locking ends which will lead to more loosening. IMHO it's dangerous to have on your setup. I really wish lee would let you custom setup your packages with the best of the best parts, I've added about $20 worth from their replacement parts catolog that have made it an excellent press and now I load 9, 40 and 45 with complete confidence.

To get rid of that chain and gain the ability to trust your powder drop, just buy these two parts.

midwayusa product/334897

midwayusa product/543877

When you buy the pro autodisk it actually comes with these pre installed and leaves the chain as the backup part (though you will never need it and it is not shown this way in the picture)

Kevin

No way I'd ditch the chain for a spring! With the spring - the arm can get stuck and you can continue cycling the press... With the chain - it's either going to pull the arm back down or break if something gets stuck. The mech is pretty much squibproof with the chain. With the spring... not so much.

If you're worried about the chain slipping through the hole, put a small "binder clip" on the arm and chain where it passes through.

[TonyT]

I'm glad that you were not injured as a result of the kaboom. I would suspect inattention to some detail during the loading process. For many years I loaded on an old RCBS A-2 single stage press. I purchased my first progressive a Dillon 550 and had the first squibs I had experienced in over 35 years of reloading. I was making up some test rounds with various powder weights and somehow my attention slipped. Since then I clear the press before chaging powder weights. In 40 S&W I tend to use WST for light loads (ca 725-775 fps) and WSF for full power loads - both are easily seen in the case before bullet seating (particulary easy to see WT since it is light grey in color). Knock wood, I have not experienced another squibb in the past 12 years. I avoid Titegroup becasue it has too many fine particles which tend to be all over the loaders shellplate and it burns too hot.

[partyboy424]

Just going to put in two parts for those of us with Lee Auto Disk Dispensers. That dog tag chain that it uses is a truly terrible design, it can loosen causing erratic powder charges and get hung up and snap. Which will cause you to lose the locking ends which will lead to more loosening. IMHO it's dangerous to have on your setup. I really wish lee would let you custom setup your packages with the best of the best parts, I've added about $20 worth from their replacement parts catolog that have made it an excellent press and now I load 9, 40 and 45 with complete confidence.

To get rid of that chain and gain the ability to trust your powder drop, just buy these two parts.

midwayusa product/334897

midwayusa product/543877

When you buy the pro autodisk it actually comes with these pre installed and leaves the chain as the backup part (though you will never need it and it is not shown this way in the picture)

Kevin

No way I'd ditch the chain for a spring! With the spring - the arm can get stuck and you can continue cycling the press... With the chain - it's either going to pull the arm back down or break if something gets stuck. The mech is pretty much squibproof with the chain. With the spring... not so much.

If you're worried about the chain slipping through the hole, put a small "binder clip" on the arm and chain where it passes through.

I think you have an understanding of how the spring works incorrect. If you see how it's setup (pretty tough to understand from google images) there's no possible way for it to bind up and the user to continue working the press. If it did bind up then the case would not be able to move up during the downstroke causing the press to lockup. At this point something would break if forced, which like I said, when you get an understanding of how it's actually setup (much different than the chain) this would not be possible to occur.

[Yardbird]

Just going to put in two parts for those of us with Lee Auto Disk Dispensers. That dog tag chain that it uses is a truly terrible design, it can loosen causing erratic powder charges and get hung up and snap. Which will cause you to lose the locking ends which will lead to more loosening. IMHO it's dangerous to have on your setup. I really wish lee would let you custom setup your packages with the best of the best parts, I've added about $20 worth from their replacement parts catolog that have made it an excellent press and now I load 9, 40 and 45 with complete confidence.

To get rid of that chain and gain the ability to trust your powder drop, just buy these two parts.

midwayusa product/334897

midwayusa product/543877

When you buy the pro autodisk it actually comes with these pre installed and leaves the chain as the backup part (though you will never need it and it is not shown this way in the picture)

Kevin

No way I'd ditch the chain for a spring! With the spring - the arm can get stuck and you can continue cycling the press... With the chain - it's either going to pull the arm back down or break if something gets stuck. The mech is pretty much squibproof with the chain. With the spring... not so much.

If you're worried about the chain slipping through the hole, put a small "binder clip" on the arm and chain where it passes through.

I think you have an understanding of how the spring works incorrect. If you see how it's setup (pretty tough to understand from google images) there's no possible way for it to bind up and the user to continue working the press. If it did bind up then the case would not be able to move up during the downstroke causing the press to lockup. At this point something would break if forced, which like I said, when you get an understanding of how it's actually setup (much different than the chain) this would not be possible to occur.

I thought it was just a return spring. If not then I apologize. The chain has never broken and has worked great for me for over a decade.

[Yardbird]

Just going to put in two parts for those of us with Lee Auto Disk Dispensers. That dog tag chain that it uses is a truly terrible design, it can loosen causing erratic powder charges and get hung up and snap. Which will cause you to lose the locking ends which will lead to more loosening. IMHO it's dangerous to have on your setup. I really wish lee would let you custom setup your packages with the best of the best parts, I've added about $20 worth from their replacement parts catolog that have made it an excellent press and now I load 9, 40 and 45 with complete confidence.

To get rid of that chain and gain the ability to trust your powder drop, just buy these two parts.

midwayusa product/334897

midwayusa product/543877

When you buy the pro autodisk it actually comes with these pre installed and leaves the chain as the backup part (though you will never need it and it is not shown this way in the picture)

Kevin

No way I'd ditch the chain for a spring! With the spring - the arm can get stuck and you can continue cycling the press... With the chain - it's either going to pull the arm back down or break if something gets stuck. The mech is pretty much squibproof with the chain. With the spring... not so much.

If you're worried about the chain slipping through the hole, put a small "binder clip" on the arm and chain where it passes through.

I think you have an understanding of how the spring works incorrect. If you see how it's setup (pretty tough to understand from google images) there's no possible way for it to bind up and the user to continue working the press. If it did bind up then the case would not be able to move up during the downstroke causing the press to lockup. At this point something would break if forced, which like I said, when you get an understanding of how it's actually setup (much different than the chain) this would not be possible to occur.

I thought it was just a return spring. If not then I apologize. The chain has never broken and has worked great for me for over a decade.

I scoped it out a bit more and it's just a return spring, so it's obvious that you misunderstood what I was saying. I stand by my first post. No powder measure sticking possible with the chain.

Sorry for the drift.

[jkrispies]

Have to admit, I had the TV going at the same time. And was sorta doing both..

This should be your biggest lesson: no distractions, and if anything distracting or out of the ordinary happens--even as simple as a primer not setting right--clear all the stations and start fresh. Whenever my wife or daughter walks in on me when I'm reloading, I immediately stop and wait for them to leave before I continue.

The first time I took out my brand new $1600 1911, about 10 rounds in I got a squib-- also my first time loading .45acp. It is embarrassing, but it's recoverable as long as you learn. Of course, your lesson was a lot bigger than mine!

Were you shooting your rounds particularly fast, or slow fire? If it was slow fire, it's a good bet that you would have noticed a squib. I'm thinking double charge, or at least an over charge like you said: you may have raised the turret halfway to check something like a primer set and just did it enough to get a full or partial charge in the brass. TG is notorious for unnoticed double charges.

In my experience, TG actually meters very well...

EDIT: Oops... sorry, didn't realize this thread was so old till I posted...

Edited March 29, 2012 by ima45dv8

[Chuckie45]

I had a semilar incedent with reloaded .40 in an XDm last weekend (Back of the case separated left the rest of the case in the camber). No majar damage thankfully. I found this interesting tid bit on Wikipedia (not always the best source of information). I know I had some casing that fit in the chamber but did not fit the go gauge. I'm leaning toward a weak and unsupported case rear.

"The .40 S&W has been noted in a number of cartridge case failures, particularly in older Glock pistols due to the relatively large area of unsupported case head in those barrels, given its high working pressure.[22][23] The feed ramp on the Glock .40 S&W pistols is larger than on other Glocks, which leaves the rear bottom of the case unsupported, and it is in this unsupported area that the cases fail. Most, but not all, of the failures have occurred with reloaded or remanufactured ammunition.[24] Cartridges loaded at or above the SAAMI pressure, or slightly oversized cases which fire slightly out of battery are often considered to be the cause of these failures.[24] Many competition shooters who reload for the .40 S&W will utilize a heavier than factory tension recoil spring to increase the lock time of the slide and prevent potential issues with early slide lock release.[25] These failures are commonly referred to as "kaBooms" or "kB!" for short.[24] While these case failures do not often injure the person holding the pistol, the venting of high pressure gas tends to eject the magazine out of the magazine well in a spectacular fashion, and usually destroys the pistol. In some cases, the barrel will also fail, blowing the top of the chamber off.

Beretta 96 Extractor Notch

While the .40 S&W is far from being the only cartridge to suffer from case failures, it is more susceptible for a number of reasons. The .40 S&W works at relatively high pressures (33,000 psi/230 MPa typical, but 35,000 psi/240 MPa SAAMI max). Since the .40 S&W is a wide cartridge for its length, and is often adapted to frames designed for the equally long but narrower 9x19mm cartridge, the length of the feed ramp must be longer to provide the same angle, which causes the feed ramp to extend into the chamber. This in turn leaves more of the case head unsupported. While this is not necessarily unsafe, it does reduce the margin of safety. When exacerbated by out of battery firing (leaving even more case head exposed) and potentially weakened brass (due to reloading) these factors appear to lead to the higher incidents of chamber failure. The number of case failures in the .40 S&W is serious enough that Accurate Arms no longer recommends reloading of .40 S&W cartridges for firearms without complete case head support.[26]

In late 1995, Federal Cartridge of Anoka, Minnesota undertook a redesign of their .40 S&W cartridge case to strengthen internally the area of the case web. While no one at Federal will address this for the record, it has been suggested that this move was dictated by the popularity of the .40 S&W Glocks, and Federal's attempt to hedge against head/web ruptures with any of their .40 S&W ammunition.

Federal .40 S&W rounds which may contain suspect casings may be identified as follows: Lot number consists of 10 characters (mostly numbers). In the 7th position, there may be a number or a letter. If there is a number in that position, the ammo was manufactured with the old style (possibly defective) brass. If it contains the letter Y (1995) or R (1996), the ammo has the redesigned casing and should be okay. If the letter H appears, then check the next three digits (the last three in the lot number). Ammo lot numbers H244 or below have the old style casings. Lots H245 and above have the new style casings.

This information was provided by Federal Cartridge Company in September 1996.

Writer Walt Rauch first brought forth information that bullet set-back (such as often occurs in administrative unloading/loading) in the .40 S&W could raise pressures exponentially. Rauch published some specific information on this set-back issue in the May/June 2004 Police and Security News, in a feature entitled Why Guns Blow Up!: "The simple chambering and rechambering of a cartridge does push the bullet back into its case."

Hirtenberg Ammunition Company of Austria (at the request of GLOCK, Inc.) determined that, with a .40 caliber cartridge, pushing the bullet back into the case 1/10 of an inch doubled the chamber pressure. This is higher than a proof load. This can occur with but one chambering since it is dependent on how well the case was crimped or sealed to the bullet."

[TonyT]

I wonder if you had a squib/reduced load which went partly into the barrel unnoticed and then was followed by a normal load.

A fellow shooter had that happen to his 1911 in 45ACP and never noticed the squibb/reduced load. Then hefound that he could not open the slide. Luckily the 45ACP is a low pressure cartridge and he bulged the barrel but did no other damage. In a 40 S&W that would have become the disaster you describe.

Edited May 10, 2012 by TonyT

[FightFireJay]

No amount of bullet setback is going to produce that type of catastrophic pistol failure. What you have described sounds like a double-charge.

Titegroup is a great powder to use in .40 S&W but, personally, I would never recommend a newbie reloader to use this as their first powder. As you have learned (the hard way) TG is not tolerant of any sort of mistake.

Why not? If the bullet set's back far enough you could easily increase the pressure by 50% or even more. In fact, I'm pretty sure I read that heavier bullets (180 and especially 200 gr) in 40 S&W are extremely susceptible to pressure increases due to small changes in over all length. This is because a small change in length is a larger percentage of difference than a lighter bullet that has more case volume left after loading.

I'm not say that his gun blew up because he had set back, but I certainly think it's possible to blow up any gun with a fast burning powder and enough setback.

[Poppa Bear]

I think you already found your problem if you could get setback on your loads with hand pressure. If you have a caliper I would check your sized case to see if it is .419 or less. The bullet is .400 and the case walls should be .010, so the bullet with case walls should be .420. If the case is at around .4185 to .4190 OD then when you bell the mouth it will allow the bullet to slightly open the case up that fraction needed to bring it up to .420 and provide tension on the bullet. If the sized case is .420 or larger then you are not getting any tension on the bullet and are relying on the crimp to hold the bullet in place.

A second possibility for the KB is too little powder. If you undercharge the case it is possible for the powder to detonate rather than burn. This leads to a very high sudden pressure spike that exceeds the SAAMI specs for the cartridge. The undercharge in this case would probably have to be around 1/4 to 1/2 of the expected charge. I cannot say for sure because I have no intention to experiment with how far I can undercharge a case before it wants to detonate.

[theycallmeingot]

I think you already found your problem if you could get setback on your loads with hand pressure. If you have a caliper I would check your sized case to see if it is .419 or less. The bullet is .400 and the case walls should be .010, so the bullet with case walls should be .420. If the case is at around .4185 to .4190 OD then when you bell the mouth it will allow the bullet to slightly open the case up that fraction needed to bring it up to .420 and provide tension on the bullet. If the sized case is .420 or larger then you are not getting any tension on the bullet and are relying on the crimp to hold the bullet in place.

A second possibility for the KB is too little powder. If you undercharge the case it is possible for the powder to detonate rather than burn. This leads to a very high sudden pressure spike that exceeds the SAAMI specs for the cartridge. The undercharge in this case would probably have to be around 1/4 to 1/2 of the expected charge. I cannot say for sure because I have no intention to experiment with how far I can undercharge a case before it wants to detonate.

in light of this thread, i have a question.

When I first got my 550b, I watched videos on it. Brian's, actually. He went through every step, and i followed every part, and was making bullets successfully without knowing why or how they worked, except that i followed the video and they worked. One thing i kept on hearing from people was "oh, you don't need any crimp on semi-auto cases. Only hot revolver loads." I heard this from multiple people, and never listened, because that's not what Brian said to do. I had forgotten about that, and now I wonder why anyone would ever recommend not crimping? I use 356 diamter 9mm LC bullets, and i can still cause set back with no crimp with my hand. It's not easy.. but I can definitely do it.

Now that i've been doing it for a couple years, crimp is something I pay attention to everytime I set up a new set of dies, and I've never had any problems just crimping to what the book recommends. Sometimes more or less, with certain strange bullet molds.

Anybody else heard this logic? Or has a reason as to why people say it?

[Poppa Bear]

I think you already found your problem if you could get setback on your loads with hand pressure. If you have a caliper I would check your sized case to see if it is .419 or less. The bullet is .400 and the case walls should be .010, so the bullet with case walls should be .420. If the case is at around .4185 to .4190 OD then when you bell the mouth it will allow the bullet to slightly open the case up that fraction needed to bring it up to .420 and provide tension on the bullet. If the sized case is .420 or larger then you are not getting any tension on the bullet and are relying on the crimp to hold the bullet in place.

A second possibility for the KB is too little powder. If you undercharge the case it is possible for the powder to detonate rather than burn. This leads to a very high sudden pressure spike that exceeds the SAAMI specs for the cartridge. The undercharge in this case would probably have to be around 1/4 to 1/2 of the expected charge. I cannot say for sure because I have no intention to experiment with how far I can undercharge a case before it wants to detonate.

in light of this thread, i have a question.

When I first got my 550b, I watched videos on it. Brian's, actually. He went through every step, and i followed every part, and was making bullets successfully without knowing why or how they worked, except that i followed the video and they worked. One thing i kept on hearing from people was "oh, you don't need any crimp on semi-auto cases. Only hot revolver loads." I heard this from multiple people, and never listened, because that's not what Brian said to do. I had forgotten about that, and now I wonder why anyone would ever recommend not crimping? I use 356 diamter 9mm LC bullets, and i can still cause set back with no crimp with my hand. It's not easy.. but I can definitely do it.

Now that i've been doing it for a couple years, crimp is something I pay attention to everytime I set up a new set of dies, and I've never had any problems just crimping to what the book recommends. Sometimes more or less, with certain strange bullet molds.

Anybody else heard this logic? Or has a reason as to why people say it?

We are actually talking about two different things here.

1. CRIMP; that force necessary to remove the bell and turn the case into a straight walled case.

This is the common style of crimp we use when reloading most of out 9, 40 and 45 rounds. We just want to remove the bell.

2. CRIMP: that force necessary to move a portion of the case into the bullet itself.

Two is the common one for high powered revolvers etc. where you want to prevent the bullet from setting back during heavy recoil. By rolling the crimp into the bullet you create a sharp edge that catches on the bullet. It is more common on rifle cartridges where the bullet will have a cannelure that the case is crimped into. Again this is because of the heavy impulse created by the rifle being fired and the desire to prevent the bullet from setting back and creating a dangerously short OAL.