Question about crimping and OAL

[PAcanis]

I've been working on setting up my 550 and have come to the crimping stage. I am using Dillon .45 acp dies.

I've been turning the die in further, have a neck size of .472 (the recommended few thousandths smaller) and am still having the bullet pushed into the case when I rack a round in my Gold Cup National match. OAL is 1.275, just what the book says it should be for 230 gr jacketed round nose.

Brian suggested I call Dillon, so I did. I was told to make my OAL 1.260...

Now I know we aren't supposed to get our information for reloading off the internet. Everyone always throws in the "refer to a reloading manual" disclaimer it seems, but does this sound right? Why would Dillon say 1.260 and Lyman's 49th edition say 1.275? How is a guy supposed to know what he can and cannot vary? I thought it was a matter of the crimping die not being set low enough and here it's (supposedly) a matter of the OAL being too long. I am totally confused. I didn't have this problem when I was reloading for my .44 mag 25 years ago, lol.

[polizei1]

The OAL isn't a "set number" and can vary. Just because someone gives you an OAL or a book states it, doesn't mean that's what you should use. I don't reload .45, so I can't help you on an OAL number. What a lot of people do, is to load an EMPTY case with a bullet and apply no-crimp. Then, put the round in your magazine and load it into the chamber. That will give you the max OAL for that specific gun. Back off the OAL ~0.005" and you should be good. Another way to do it is to pick a few different OAL's and shoot them, and see which one is more accurate.

For example, for 9mm, the OAL can vary between 1.100" and 1.160" or more. When I was testing loads, I set the OAL at 1.13, 1.14, 1.15, and 1.16. My current USPSA load is 1.140." Given the amount of powder I was using, it was the most accurate combination. Long story short, there is no "set number."

Edited September 7, 2012 by polizei1

[PAcanis]

If there isn't a set number for OAL, is there a set minimum OAL?

Doesn't seating the bullet further into the case build up pressure? How does one know how far he can seat the bullet, or in other words, shorten OAL from what the manual says?

[The_Vigilante]

Just use Dillon's number of 1.260. Work up a dummy load using this OAL. Barrel check it-if it drops in freely, turns freely, and drops out freely then the OAL is OK. Crimp would normally be around .469-470

Edited September 7, 2012 by The_Vigilante

[superdude]

OAL varies depending on the source. For example, Hornady recommends an OAL of 1.230 with their 230 grain RN bullet. Speer says 1.260. Sierra say 1.270.

The first thing you have to determine is if your OAL will fit in your barrel's chamber. The best way to do that is to remove the barrel and do the "plunk" and "rotate" tests. The round has to drop in and OUT of the chamber freely, and when in the chamber it must be able to rotate freely. This tests whether the bullet is touching the riflings.

How far is the bullet being pushed into the case when chambered?

more information on OAL can be found here:

http://38super.net/Pages/Overall%20Length.html

[Bob DuBois]

Crimp dosen't hold the bullet the first stage sizing die holds the bullet. crimp helps it to feed into the chamber. May be the sizing die is not set correctly. First stage sizer should just kiss the shell plate on 550's I like to use a small strip of paper as a go no go gauge. Should pull out on the paper but not push in with pressure on the operating handle. If the die is set correctly and the bullet still turns might try another brand of dies. I'm a fan of Lee's first stage sizer. Outstanding primer punch design and Lee's sizing die will size closer to the extractor groove than some other brands, use them in my Dillon 550 and 650 with Great results. Lee's four carbide die sets are on sale at Midway USA this month under forty bucks.

When setting up a new machine for a test of OAL, check the first few rounds to see if they will go in your magazine with enough clearance to feed. Either remove the barrel or use a chamber gauge to see that the round drops a few thousands under the hood of the chamber. I shoot 200gn cast bullets in my 1911's and like an OAL of 1.250.

It's hard to read but crimp on a 45 should be .468 to .470. Loading auto cartridges is a little harder than the revolver rounds but very rewarding once you get it dialed in.

[Seeker]

The Manual list the Max COAL, 1.275" Without going into great detail, a good rule of thumb is to use a trusted factory round using the same weight and bullet profile for your initial Cartridge overall length. Another rule of thumb is that the crimp should be bullet diameter + .02 (twice the wall thickness of an average brass. As an example Full Metal Jacket Bullet diameter = .451" +.02"= crimp diameter =.472" Average Length of Winchester White Box 230FMJ 1.260"

For 230 Grain Round nose bullets I use a COAL of 1.255" to 1.260".

The Hornady 8th edition has a recommended COAL for the 230gr FMJ RN is 1.230" The Maximum length is 1.275"

Some pistols perform better with the load a little shorter, some a little longer, but do not exceed the min/max specifications.

You will find that Hollow points, SWC, Flat points, different bullet weights etc. will all need a different length.

As a warning, extreme bullet setback can cause high pressures which WILL result in very un pleasant results.

It's always prudent to have a trusted seasoned reload friend walk you through the first batch of rounds.

[PAcanis]

Fantastic feedback, guys.

Is this wide variance of OAL limited to straight walled pistol rounds, or can I expect the same when I begin to load for my Garand?

[PAcanis]

Forgot to say, I didn't measure OAL of a round that had the bullet pushed in when racking it, but the bullet was in far enough that the round nose had a gap between it and the case.

[Dirty Rod]

If there isn't a set number for OAL, is there a set minimum OAL?

Doesn't seating the bullet further into the case build up pressure? How does one know how far he can seat the bullet, or in other words, shorten OAL from what the manual says?

There is a min for every caliber. I believe SAAMI specs a min of 1.190 for .45 ACP. As mentioned above, different vendors and loads can range from min to the max of 1.275 for .45. What's listed in the book is what was tested. Most factory cartridges are loaded shorter than max to ensure that they feed in all of the various pistol chambers. You may also find that a 1.275 round does not eject properly on some guns. If you do shorten the round pressure will increase so you shorten slowly and test until it functions reliably. A couple of thousandths won't be a problem unless you are close to the max charge. Most folks find the perfect OAL first and then work up their charges. If 1.275 works in all your guns then you don't HAVE to shorten it but you will probably gain some reliability if you do. As stated, just drop your charge back down some and work up slowly.

Is this wide variance of OAL limited to straight walled pistol rounds, or can I expect the same when I begin to load for my Garand?

Yup. With magazine fed cartridges you will probably find that most folks load to the max length that the mag will accept and stop there. Bolt guns and rounds for single fed AR's can be all over the range depending on who's book you use.

Edited September 7, 2012 by Dirty Rod

[PAcanis]

Where can I find these SAMMI specs? It seems like good info to have on hand if I change to a different weight and style of bullet.

I did shorten the OAL to 1.262. I figured I'd give myself .002 play before hitting .260 and it cycled through my pistols fine. Looks like it's on to the powder and primers!

[PAcanis]

Looks like I've got some more questions. Please bear with me.

Before I even got my reloader I picked up some powder. I did a search and saw Titegroup was recommended quite frequently for being a good all around powder to use in different pistol cartridges. The gun shop had some, so I bought some. The problem is, I do not see it listed specifically for 230gr FMJ round nose. At least I don't think it is. I haven't gotten a firm grip on all the acronyms yet.

This is from Hodgdons site.

FP, that's flat point, right? Or what I call truncated?

And LRN I'll assume is lead round nose.

So why shouldn't I use this powder for 230gr ball ammo?

And in the chart is has "COL" listed. Is that the same as OAL? Maybe Cartridge overall length? So it is telling me I can seat the bullet down to 1.200?

So what if I am not using Hornady bullets as the chart lists?

[superdude]

Where can I find these SAMMI specs? It seems like good info to have on hand if I change to a different weight and style of bullet.

I did shorten the OAL to 1.262. I figured I'd give myself .002 play before hitting .260 and it cycled through my pistols fine. Looks like it's on to the powder and primers!

http://www.saami.org/specifications_and_information/index.cfm

click on the SAAMI/ANSI standards. Then select which you want: pistol/rifle/rimfire/shotshell.

[BSeevers]

I check to see if a bullet will seatback by holding on the brass, place bullet against bench and lean into it. If it can handle that it can handle a slide.

Be careful as you use the fast powders like titegroup. You could blow a 45 case with bullet seatback or too small OAL. When I loaded and shot 45 i used 1.250 for everything and that was with the crappy powders we had in 80's My first year I kept track I shot 57,000 of 200 H&G SWC lead 1.250 with 5.7 grains of 231 if I remember right. It was power factor of 180 plus. I never use a reloading manual since your average M on here has loaded 100,000 plus plus of the loads I that I would use and be.com is a better source of information.

. If I was a more of a casual or shot a lot of different loads and guns that would be different and the manual would be my best friend, to start.

[PAcanis]

Excellent website superdude. Thanks.

So as long as your length falls inbetween the min and the max you are OK, no matter the grain bullet?

[PAcanis]

Thanks for the tip on checking my crimp, Bill. You won't find a good tip like that one in any manual.

[superdude]

Looks like I've got some more questions. Please bear with me.

Before I even got my reloader I picked up some powder. I did a search and saw Titegroup was recommended quite frequently for being a good all around powder to use in different pistol cartridges. The gun shop had some, so I bought some. The problem is, I do not see it listed specifically for 230gr FMJ round nose. At least I don't think it is. I haven't gotten a firm grip on all the acronyms yet.

This is from Hodgdons site.

FP, that's flat point, right? Yes. Or what I call truncated?

And LRN I'll assume is lead round nose. Yes.

So why shouldn't I use this powder for 230gr ball ammo? You can.

And in the chart is has "COL" listed. Is that the same as OAL? Yes. Maybe Cartridge overall length? Yes. So it is telling me I can seat the bullet down to 1.200? That OAL is what they tested that specific bullet at. That OAL does not apply to all bullets.

So what if I am not using Hornady bullets as the chart lists?

These are all good questions. Here's the scoop: Load data in manuals shows exactly what bullet they used and exactly the OAL they loaded for their tests. Technically, that data is specific to that bullet and OAL - and specifically their test gun (only!). Also, the data apply to the lot number of the gunpowder (minor burn rate/density differences) and applies only to those specific brand/type of primers (spark intensity). And to their brass as well (case capacity).

The data are guidelines. If you're using the same components, then your results should be similar. But velocity (and pressure, and accuracy) can be different simply because your barrel is different. Seriously! Much has been written on this and it is extremely well documented.

We all end up interpolating from load data from different manuals. These manuals include those from bullet and gunpowder manufacturers. We seldom use the exact same components, and some manufacturers just say "use the same data as lead bullets" - I'm think of some plated bullet makers. The message here is that there is some leeway in loading practices - just don't get crazy.

OAL length varies for many reasons, as noted in the link I posted above. It's hard to give fixed numbers because of that. Gun A might prefer an OAL of 1.275. Gun B might choke on that, and required an OAL of 1.40 for the same bullet. Gun C might require something different. That is reality.

It's good that you're paying attention to detail. That is required (everytime!) to produce quality, safe ammunition. However, you also don't want to other-think these issues. A manual might state an OAL of 1.250. But you could probably run it anywhere from 1.220 to 1.275 and never know the difference.

The real concern when loading ANYTHING is pressure. Too much can be a bad thing, and that's what we try to avoid. It is always a concern when you get to the upper end of the recommended powder charge. It's not as much of a concern at the lower end to middle range. That said, most incidents of guns blowing up are due to big errors in the loading process, like a double charge. A 10% overcharge typical won't blow up anything, unless your brass is bad, but only results in accelerated wear (from faster slide velocity). Still, you want a margin of error, so it pays to pay attention to pressure. But most guns will handle the upper pressure limit with no problem for a billion rounds. After all, they are designed to work within those specified parameters. Most factory ammunition is loaded to the upper performance range. That's why when you look at a manual you'll often note that you can't always improve much on factory ammo performance. For example, factory .45 230 grain runs anywhere from 830-880 fps. The Hornady and Sierra manuals top out at 900 fps.

Bullet profile is VERY important in determining OAL. The good thing about .45 230 RN is that they are pretty similar in profile and OAL does not vary that much for that reason. But when you switch to a flat nose profile, all bets are off because they can vary so much.

Load development... The rule of thumb is start low and work your way up. This applies every time you start a new load by switching bullets or powders or guns.

If you can't find specific data for the bullet you're using, find analogous data for a bullet of similar design. For example, data for 230 grain FMJ RN bullets will be similar and is a good starting point for your load development procedure (see above). But data from FMJ will be different from data for plated/cast/swaged even if they are all the same weight and profile.

Another alternative is to ask the bullet manufacturer if they have recommendations. Most are very helpful.

[superdude]

Excellent website superdude. Thanks.

So as long as your length falls in between the min and the max you are OK, no matter the grain bullet?

Okay with respect to what? feeding reliability? pressure? they are different issues.

OAL helps to define typical feeding reliability. But this is never a guarantee. And it depends on the bullet nose profile, which might impose it's own limits depending on your barrel's chamber. Some bullets might require a short OAL than SAAMI specs.

The maximum OAL defines the space limit of the cartridge, and gun makers have to make sure that their guns will accommodate this length. It's a "blueprint" standard. That said, some magazines might not accept a round loaded to max OAL. They might accept a RN bullet, but not a FN bullet for the reasons at the link i posted earlier. For example, my .45 Para Ordnance double column magazines won't take anything RN over 1.250 inches, as i discovered during the 3 gun nationals (ugh!). It would be even less for a FN bullet.

[Youngeyes]

Time to offer my 2 pesos. FWI I can't run my 45 at 1.275. I set at 1.25 for a colt XSE. The manual does say 1.275 but that is the number they tested that load at. You need a chronograph to really dial in a load. If you expect 750FPS and you get way less or way more, it is probably due to you changing the OAL. Rolling your own means just that. They are your own custom loads. You need to be able to test them. You can't do that without some way to measure the results. Gives you confidence when you get what you expected, or you find the next step to get to your goal. Have fun but stay safe.

[CocoBolo]

The Load tables are specific to an exact bullet, if it says Hornady XTP then in order to apply all factors you need to have Hornady XTP bullets, not a xyz snake shooter bullet.

With any bullet you need to determine the max size that will fit in the mag, then do the barrel drop check and find the max that fits in the barrel -.010 for tolerance in reloading.

45 is a low pressure round and should present much of safety issue unless you go off the deep end.

Each bullet will have a different amount of crimp required and this will vary depending on the brand of brass, so is thicker than others. I use the thumb test, ease into the crimp just a little then give it the thumb test. Thumb test, measure OAL, press firmly against bench with thumb, measure again, if it didn't move its enough. Repeat test on radom rounds thru the first 100, if they all pass you got it.

Start low work up check primers and case and crono. When you hit your target velocity, toss all rounds loaded with more powder.

[PAcanis]

You guys are great. I appreciate all the information you've given me. You've all been very helpful.

And youngeyes, you touched on my next question; how do I test pressure? I'm thinking I can't, but I can test fps with a chronograph and correlate that to pressure, right? So if I am expecting 750 fps and am only getting 625, then if I seat the bullet in further I will increase the pressure, which will in turn increase the fps. At least that's how I am interpretting it.

I'm using Raniers plated bullets. I did go to their site and see where it said to follow the data for LRN. I just wish Hodgdons was open today to talk to them about their titegroup. Maybe I'll leave that jar sit for a while and pick up some Bullseye or W231. That seems to cover a broader range of .45 acp rounds.

I'm ready to put some powder in and start loading. Lucky me there is a gun shop in my backyard. That's where I'm headed now.

[superdude]

You guys are great. I appreciate all the information you've given me. You've all been very helpful.

And youngeyes, you touched on my next question; how do I test pressure? I'm thinking I can't, but I can test fps with a chronograph and correlate that to pressure, right? So if I am expecting 750 fps and am only getting 625, then if I seat the bullet in further I will increase the pressure, which will in turn increase the fps. At least that's how I am interpretting it.

I'm using Raniers plated bullets. I did go to their site and see where it said to follow the data for LRN. I just wish Hodgdons was open today to talk to them about their titegroup. Maybe I'll leave that jar sit for a while and pick up some Bullseye or W231. That seems to cover a broader range of .45 acp rounds.

I'm ready to put some powder in and start loading. Lucky me there is a gun shop in my backyard. That's where I'm headed now.

You can't test pressure. It requires special equipment. I doubt anyone on this site has that equipment. Usually only manufacturer's labs are set up to test pressure. The equipment required and procedure is listed in the SAAMI booklet.

Your interpretation of OAL and pressure and velocity is correct. HOWEVER, you should not (never!) adjust seating depth to change velocity. adjust your charge weight. besides, adjusting your OAL can result in feeding problems. You adjust your OAL for feeding reliability, and adjust your charge weight for velocity. these are rules of thumb that are (or should be!) written in stone.

Titegroup will work fine with your plated Rainiers. No need to buy another powder. Follow their charge weights, but seat the bullet where you want. Their 1.200 is mighty short for lead RN.

[PAcanis]

... HOWEVER, you should not (never!) adjust seating depth to change velocity. adjust your charge weight. besides, adjusting your OAL can result in feeding problems. You adjust your OAL for feeding reliability, and adjust your charge weight for velocity. these are rules of thumb that are (or should be!) written in stone...

Why is that?

If the bullet is seated at 1.262, as mine are, and feeding through my pistols (at least hand cycling), but if the fps is not reading what the data chart says it should be for a given load, why couldn't you seat the bullet in another couple thou and test the load against the chronograph again? As long as it still feeds and is still above the minimum seating depth, wouldn't that get you up where the data chart you are using says you should be, and not use more powder?

[superdude]

seating a couple thousands deeper won't get you there. who knows how deep you'll have to go and who knows how much pressure will increase as a result. try not to second-guess pressure too much, bad things might happen (and have). this is why this is not the preferred method for adjusting velocity. In fact, i don't think any manufacturer recommends changing OAL to change velocity. And they literally have written the book on load development. since we don't have the equipment to measure pressure, we try to follow smart loading practices to remain safe.

velocity is different for every barrel. unfortunately we've come to expect our data to match the manual's data. in most cases it comes pretty close. but life is full of surprises and sometimes your actual velocity can be off a mile from what's published. i've seen examples of both matching and mismatching many times.

There are better ways to adjust velocity, including switching to a different powder that has a broader range to begin with. Titegroup is a fast burning powder and will show larger changes in pressure than a slower burning powder. It works fine for many applications but will be less forgiving of errors.