[Flirting with an open minor glock slide]

I use an RMR with lone wolf 6 port barrel, 11 lb spring. You'd be better off w sjc frame mount for an RMR, I use a dovetail mount.

Zev fulcrum and magwell rounds out a cheap(ish) open gun.

I run 100 GR bullets about 1300 FPS with power pistol. You'll want a slower powder and lighter bullet to work the ports / comps.

[Pleased With New Powder]

Promo is about the same as Red Dot isn't it?

Promo is red dot without the red flakes. Alliant states on their website to use red dot load data.

Good to know. I wonder why they put it out as a different powder?

Promo does not have a consistent density from lot to lot. So for every lot you need to see what bushing to use (or readjust your powder measure) to get the same throw weight. It is cheaper to produce because there is no need to control a consistent density.

[Pleased With New Powder]

I don't think you can infer the speed of a powder from the amount used in a load. I could be wrong

That is correct. Energy density of the powder also has to be taken into consideration. VV publishes theirs. Not sure about Hodgdon / Alliant.

[WHERE IS ALL THE POWDER]

All goods are scarce, some just more so than others.

I just wish the retailers would be smart enough to raise prices to control the panics rather than let their shelves go bare.

Unfortunately the shooting community gets angry and vengeful instead of being happy that products are available and go where they are valued most.

You hit the nail on the head here. Most shooters (and most consumers in general) get mad with retailers when they "gouge" on pricing. I guess most folks would rather have empty shelves and need to win a lottery to get product than pay the (inevitably higher during a shortage) market price.

Of course, when retailers don't ration by price you end up with hoarders and scalpers - neither of whom help the situation other than redirecting anger.

And when they do ration by price... Well, cheaper than dirt is still fairly unloved as far as I can tell as a result.

[WHERE IS ALL THE POWDER]

As for Varget, they had a fire in the facility and had to shut down production, probably until sometime in 2015, I think they said next summer they hope to start producing again.

I think this is clays not Varget. No issues finding Varget locally.

[929 Sighting]

Like a ... Nevermind. Yes, grabbed it.

damn you!

I will keep trolling GB hoping to get lucky.

I think that's the recipe for success. Looked at closed auctions for 929s - another sold for 1189 within 10 minutes of being posted.

I just realized you can save a search on GB and get email alerts if a new listing meets your search terms. Maybe try this with Wesson 929 as the search term.

[929 Sighting]

TK Custom already has the moon clips. And 9mm is a lot less finicky on brass / moonclip selection than 38/357 brass.

[929 Sighting]

Like a ... Nevermind. Yes, grabbed it.

[929 Sighting]

Just logged into GB before leaving work. One was put up 5 minutes earlier with BIN for 1125. Gotta love good timing.

[East Coast Xtreme Bullets Distributer?]

9 weeks?! When's the last time you ordered. I've never had an order take more than two... maybe three.

[Powder type vs percieved recoil?]

I studied engineering but ended up in a non-engineering career, so it's the opposite for me. Shooting is a chance to connect with my inner geek.

/Sits back down with Quickload and VV loading guide.

[Powder type vs percieved recoil?]

This is a good treatment. I didn't think of the explosion model. I particularly like that the weight of the handgun is taken into account - which is also obvious because a heavier handgun recoils less than a lighter one. However, wouldn't half the weight of your forearm also factor into this?

Not really. Once you get past free recoil it becomes a bit more complex. If you held a firearm as firmly as a ransom rest you'd include your whole body weight. But of course, even the best shooters shooting the flattest guns don't.

Is first model the impact of the recoiling firearm on the shooter as an inelastic collision (even though you're already holding the firearm). So the shooter has to absorb the entire free recoil of the firearm. Think of it as catching a baseball. You may start off holding the firearm, but other than the mechanics of your grip that's irrelevant. The moment a baseball hits your glove it is no different than a firearm recoiling - you absorb its energy to decelerate it.

Then it becomes a pretty crazy statics / dynamics problem that I'd need to crack a book to even start to consider.

[Glock 21 brass failure]

Yo Pete. You do know that Glocks will fire out of battery right. I guess the ones I have witnessed and the one that did in my hand didn't really happen huh.

You may have a wealth of knowledge to share, but you have a funny way of sharing here.

DougC

How do you define OOB? Barrel and slide unlocked? Or slide slightly retracted? the former is the actual definition.

What Gen? Any mods? I don't know anything about your situation. But if the primer was struck in the center (as here) then by definition the firearm did not fire OOB. The barrel needs to have swung back into place and locked into the slide to have the primer struck as shown. By the time the slide/barrel is actually OOB (ie unlocked) or before the firearm fully returns to battery, the firing pin is too far up relative to the case head to hit the primer as shown.

While I'm a Gen 4 guy these days, none of my firearms will so much as click / no bang before the slide / barrel are well locked up.

hi petethefish,

so when I mention that the original poster may want to check his pistol for firing out of battery,

you said it was not possible.

now you are asking what mods were made?

miranda

No. Again, reading comprehension. That was a response to a new poster.

[Glock 21 brass failure]

Yo Pete. You do know that Glocks will fire out of battery right. I guess the ones I have witnessed and the one that did in my hand didn't really happen huh.

You may have a wealth of knowledge to share, but you have a funny way of sharing here.

DougC

How do you define OOB? Barrel and slide unlocked? Or slide slightly retracted? the former is the actual definition.

What Gen? Any mods? I don't know anything about your situation. But if the primer was struck in the center (as here) then by definition the firearm did not fire OOB. The barrel needs to have swung back into place and locked into the slide to have the primer struck as shown. By the time the slide/barrel is actually OOB (ie unlocked) or before the firearm fully returns to battery, the firing pin is too far up relative to the case head to hit the primer as shown.

While I'm a Gen 4 guy these days, none of my firearms will so much as click / no bang before the slide / barrel are well locked up.

[Powder type vs percieved recoil?]

This is interesting. I just had this conversation today with a friend at a match. The math and physics aren't too obtuse. Recoil is nothing more than the kinetic energy of accelerating the bullet down the barrel. Newton's law states F=ma, or Force equals mass times acceleration. Acceleration is mass times the square of velocity divided by 2 so Force as a function of velocity is F=1/2mv^2 when accelerating a thing from rest - since the bullet isn't moving before you shoot it, this equation works.

F=1/2mv^2. That is correct. Everything about the way you go there is wrong. Acceleration does not equal "mass times the square of velocity divided by 2". The only similar formula that is applied to acceleration is to measure distance under constant acceleration and does not involve mass.

And in the case of a firearm, when we're talking about Force, we're talking about Kinetic Energy. The Kinetic Energy of the total system (bullet + recoiling gun + heat + noise) = The Potential Energy in the powder charge & primer.

So now there's two things to discuss. First, the heavy bullet slow speed, vs light bullet high speed recoil analysis. Just looking at the equation, we can see that Force (recoil) doubles when we double the mass of the bullet but increases by a factor of 4 if we double the speed.

For a minor power factor of 125,000 using a 147 gr bullet going 850 fps we get 53,103,750. For the 113 gr bullet going 1106 fps, we get 69,112,834. We'll ignore the units since they're the same for both. What we see here is that even though both rounds make 125k PF, one has almost 30% more recoil.

This is incorrect. You're assuming that Kinetic Energy of the recoiling firearm is equal to Kinetic Energy of the bullet. It is not. The only place Kinetic Energy is conserved is as above - Kinetic Energy of the system after firing the bullet is equal to Potential Energy in the Powder & Primer.

The correct physics model to apply to the system after the bullet leaves the gun is that of an explosion. In other words, momentum, not kinetic energy, is conserved. Momentum = mv, so doubling the speed of the bullet doubles the recoil of the gun (caused by the bullet), just as doubling the mass does.

As I noted in my previous post here, the model would be M1V1 = M2V2 + M3V3 where;

M1 = Mass of Firearm

M2 = Mass of Bullet

M3 = Mass of Powder Charge

V1 = Velocity of Recoiling Firearm

V2 = Velocity of Bullet

V3 = Velocity of Gases Escaping from Firearm

As a result, your calculations about recoil increase are totally off base. Of course, that should be obvious! A 30% increase in recoil is the difference between a 9mm and a .45. The difference between a 115 & 147 at minor PF is nowhere near that large. Let's use some actual loads I have used with similar velocities as you gave. We'll asume that Gas Velocity is twice bullet velocity - quickload has some estimates, but I don't have it open now.

Berrys 115 GR RN, 5.6 GR Power Pistol, AVG Velocity = 1165 FPS (~ 134 PF).

Zero 147 GR FMJ, 4.3 GR Power Pistol, AVG Velocity = 905 FPS (~133 PF).

For the first load, recoil impulse to the firearm = (115 * 1165) + (5.6 * 2320) = 146,967

For the second load, recoil impulse to the firearm = (147 * 905) + (4.3 * 1810) = 140,818

This shows that the lighter load has a 4.4% greater recoil impulse than the heavier load - that's a little closer to reality! Now let's take it a step further. Mass of the firearm is static - lets assume it weighs 2 lbs, or 14,000 Grains.

For the first load, velocity of the recoiling firearm = 146,967 / 14,000 = 10.49 FPS

For the second load, velocity of the recoiling firearm = 140,818 / 14,000 = 10.06 FPS

Now, the recoiling firearm does have kinetic energy that we have to absorb, so the Kinetic Energy for each load is;

First load: 1/2 * 14,000 * (10.49 ^ 2) = 770,280 (non-standard units)

Second load: 1/2 * 14,000 * (10.05 ^ 2) = 702,802 (non-standard units)

So the increased Free Recoil (KE of Firearm) of the lighter load is 9.6% greater than that of the heavier load.

What the shooter feels is probably somewhere in the middle of those numbers.

So, how does this apply to powders? We know from the Powder Burn chart that certain powders burn faster than others. For instance, Titewad is faster than Titegroup. So, even though we don't know what the flame front speeds are (well, maybe someone does, feel free to post up if you've got it) we at least can extrapolate that the slower powders will, in fact, without doubt, recoil less. Will that difference be perceptible? I dunno. The bullet's are for sure, but I don't know about the powders. I tend to think that the greater part of the recoil is the bullet part, but, the flame speeds are MUCH higher, probably on order of 30,000 fps or more.

Maybe we can talk one our ChemE members to discuss flame speeds.

H

Pretty simple. To reach a given velocity, with a given projectile, requires less powder the faster that powder is. So your conclusion is incorrect; slower powders (for a given firearm, projectile, and velocity) recoil MORE than fast powders.

Flame front speeds have nothing to do with this. The velocity of gases (which consists of the burned and unburned powder charge) escaping from your barrel are however key, and there is software available that models this.

[Extreme Hallow Point for Major]

They would stick in the chamber when I would unload, show clear. I was shooting an open glock with a Kkm barrel and loading as long as I could

That's more of an issue w/ your recipe / equipment than the bullets, no? I had a similar issue w/ my 9mm Bowling Pin load, but just had LW ream the leade a little further & no more issue...

[Glock 21 brass failure]

hi peterthefish

In the way I talk to so many.

Lets you an I come to terms.

If you want to insult me you are going to have to be more clear.

you seem to think I am some kind of authority.

I have to thank you for the credit.

Well now isn't that folksy and cute. Let's come to terms Miranda. Let me be clear. I think you've added nothing of value to this discussion, and I think that's probably par for the course for you in just about all your endeavours. I don't think you're any type of authority on anything. I think you embody everything about idiots on the internet who read about 'out of battery firing' and 'tolerence stacking', apply a little bit of the type of 'common sense' you seem to think you have but the engineers who design these products lack, and come up with novel realizations that everyone else in the world has somehow missed.

You on the other hand seem to own a Glock.

So I am thinking you have a reading comprehension disorder of your own.

It never hurts to know where your equipment is weak....

If the brakes on your car are weak you should re-engineer them before you go road racing.

Knowledge is power.

There are reasons there are aftermarket Glock barrels.

You should make an attempt to look at the features listed.

miranda

I'm not sure how me owning a Glock (actually many Glocks) translates into a reading comprehension problem? I also own Sigs, HKs, Walthers, S&Ws, FNs, and many more that don't immediately come to mind. I guess by your criteria I'm not qualified to comment on any of them, but you are. What an interesting and non-sensical world you must live in.

It never hurts to know where your equipment is weak....

If the brakes on your car are weak you should re-engineer them before you go road racing.

Knowledge is power.

There are reasons there are aftermarket Glock barrels.

You should make an attempt to look at the features listed.

miranda

Any firearm that is not a revolver will have a partially unsupported chamber. All brass is thick at the case web and thin near the mouth. Again, your little experiment in bisecting the case adds nothing. While early Glock 40s had a chamber with less support than most, that is no longer the case with ANY factory Glock barrels. Shooting .45 loaded to safe pressures will cause no issue in ANY Glock .45.

In addition to Glocks, I own several aftermarket Glock barrels. OP isn't shooting 9 Major - in other words, he's not going road racing, he's going to the corner store, and even though he still has small discs up front and drum rears, they're fine for what he's doing. His stated load is (at first glance) a safe one. I don't need to 'look at the features listed'. I own and am familiar with the equipment, as well as reloading.

You seem to be familiar with parroting nonsense about Out of Battery firing and 'Tolerance Addition' when the limit of your expertise is what you've read online. I pointed out previously why OOB is simply a non-possibility here, and anyone familiar with the way modern firearms (in general) work would understand that.

But please, let's come to terms. You're an idiot. You have nothing to contribute here and are simply taking up space with your poorly written posts that are completely free of meaningful contribution on the topic at hand.

[Glock 21 brass failure]

while yall was talking I went into my basement

and cut a CBC 45 auto case in half.

( it was harder to do than I expected )

you can blame a weak case if you want.

most of the case can't hold up to launching a 45 round.

So the question begins to arise where on the brass case can you expect

to hold the 23k PSI ?

(this site says 23,000 psi...http://www.handloads.com/misc/saami.htm)

from what I see the extraction groove ends at just about the same height

as the bottom of the case interior.

this leads me to think the chamber should support the case

up to the extraction groove.

you, of course, may think otherwise.

so what do you think is a good plan of action?

build a chamber that is close to the weak limits of the case

and make sure the case is a far back in the chamber as possible?

I think I can see enough tolerance addition to get to the weak edge of the case.

miranda

miranda

I see you are continuing with reading comprehension issues. Aside from your gross mischaracterization of my prior post, 23K PSI is the 45 +P spec.

But I think you're really on to something here. Maybe you should take a pic of that case you cut and send it to Glock. They've probably never seen one before - this could help them understand how the brass looks and where it looks like its weak so they can design their chamber right.

You should probably also let their engineers know that you've hear of something called tolerance addition and that you think it might also cause problems. I'm sure they'd appreciate it.

[How hard is it to convert a revolver to 9mm?]

I would need a 9mm barrel to get accuracy unless you want to load .357 diameter bullets in the 9mm case. For a 9mm barrel, I would go with a Walther 1 in 10 twist. This is a barrel blank that has to be turned down, threaded, etc. The twist isn't 1 in 10, but a close metric equivalent. The grooves are .355, correct for a 9mm bullet.

All of my modern S&W .357s also have .355 grooves, which is SAAMI spec. But an older one may be questionable. The twist rate is the only difference.

You can shoot .357 diameter bullets from 9mm cases but I notice no difference in accuracy using 9mm bullets in 38 SC in my 627.

Making 165 would be tough but doable - you can load long. But if you want to make major with a 6 shot better off with a 625.

[How hard is it to convert a revolver to 9mm?]

I've been thinking about picking up an old Smith like a model 64 or something or maybe a used Ruger Gp100 and sending it off to a smith to get converted to shoot 9mm from moon clips so I can have an ESR gun that isn't the 625.

I mean I know I can get a 38 special gun to use moon clips but I would like to keep my caliber selection down and also I kind of like the idea of being different.

So I guess my quesiton is how hard is it to take a gun in 38/357 and have it rebarreled and re chambered for 9mm? Do people make 6 shot 9mm moon clips? And more importantly assuming any of this is doable who would do it? Who is the go to guy for revolver work?

Look at the TK Custom website. No problems machining a .357 to 9mm. Not sure about pressures with a .38. No need to re-barrel - SAAMI spec for land and groove diameter is the same for .357 and 9mm. Twist rates are different but as long as you use heavier bullets with the 9mm you'll be fine. He even sells moonclips.

[Extreme Hallow Point for Major]

Is anyone running extreme Bullet Hollow Points in a Open gun? Any luck or do I need to stick to the hard plated?

Their HPs are thick / hard plated.

[Glock 34 zev trigger]

If you just shoot local stuff nobody will say anything. But if you wanted to be legal you'd have to get the ZEV Trigger that has the Glock OEM Trigger Pad. If you haven't used it yet they'll swap it out.

thanks for the reply. Appreciate it.

So in theory i can swap the trigger pads from the kits and be a happy legal camper.

I don't believe you can just swap out the pads - you'll need to swap out the trigger assembly including the trigger housing, as I believe the ZEV trigger with the OEM pad has over-travel adjustment on the trigger housing, vs. the trigger for the Fulcrum.

[Glock 21 brass failure]

ah. ok propagation of misinformation.

That's me, using logic and facts to propagate misinformation...

I said it was my guess. Iffin I had the pistol in hand, I would not be guessing.

So you want me mention how to use a pencil to test if a firing pin will strike?

you seem pretty knowledgeable why don't you tell us your test?

saami specs are interesting. There is only one spec that would concern me here.

How far back can the case be in the chamber and still allow the pistol to fire.

I am a big believer in the simplest answer is usually the answer.

so real quick

what causes case failures?

unsupported cases

too much power

weak cases from corrosion

Corrosion usually produces 2 piece case failures.

that case looks pretty straight for a corrosion failure.

you can also see the stamp mark of the chamber edge.

He said he KNOWS the was no double charge.

that leaves unsupported...

This pistol should be checked.

Some one else here mentioned another type of barrel as a fix.

I don't know about you but I don't shoot pencils out of my guns. I shoot bullets which are propelled by a powder charge ignited by a primer. So I use primed cases in my test.

I'm not even sure what you mean by "How far back can the case be in the chamber and still allow the pistol to fire." Are you assuming an open chamber here?

Corrosion usually produces 2 piece case failures? Really? And those are the only causes? No possibility the brass was work hardened excessively, defective, or previously bulged with an excessively hot load?

Let's take a look at the primer strike. Looks pretty centered to me. Now, since the barrel drops when the slide unlocks (ie goes "Out of Battery), we know that had it fired OOB the primer strike would be well off center. It's not. In fact, it's exactly in the same place as primer strikes made by my Glock .45. Which, by the way, will not lock into battery with even a .004 shim between the back of the locking block and the slide.

Just like in House the answer is never lupus, the answer here is almost never OOB.

Everyone knows they didn't double charge. Just like no kabooms are ever caused by reloads - it's always the last round in a box of factory ammo with the box long since thrown away.

But N310 is a fast powder with poor case fill in a 45 under a heavy bullet where small variations in charge weight would not be apparent but could be catastrophic.

[WHERE IS ALL THE POWDER]

Scarce goods must be rationed.

Good grief... Let's bring the word "ration" into the discussion Rationing sounds like the government would be involved.

If the government were involved I would need a background check and pledge that I was mentally sound before buying a pound of powder. Of course if I wanted two pounds within 7 days of each other it require and form and another fee. If my powder was too fast or too slow it would require a $200 tax stamp and 6-12 month wait.

Let's just call it the law of supply and demand

It's an economic term used to describe methods for allocating scarce goods. Read into it what you will.

[WHERE IS ALL THE POWDER]

Scarce goods must be rationed. Either by price (ie those who can afford high prices win) or time value (ie those who have the free time to click refresh on Gunbot all day win). Neither is intrinsically more fair than the other. Both have their merits.