Technical question about 9mm ammo fired out of a revolver

C

Concerned Citizen

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I always wanted a snubnose revolver that can shoot 9mm so I recently bought one. I intend to include it in my carry rotation once I get the TK Custom moonclips for it.

I've heard about some cases where a 9mm bullet has loosened forward from it's case from the force of recoil out of a revolver and locking up the cylinder, a platform where 9mm behaves differently then it does in the design it was intended for, a semi-auto. So naturally, I want to avoid this as much as possible.

My question is which 9mm bullet is less likely to loosen under force of recoil out of a revolver, the lighter ones or the heavier ones? I'm talking about quality, professionally produced self defense ammo only here, not Uncle Bob's reloads. This is also not about which make/model of 9mm that you think is the better manstopper, it's a physics question.

I asked this on two other forums and surprisingly, only one person was able to give me a straight answer. He said that the lighter bullets would be less likely to loosen because they have less inertia. Huh? This doesn't seem to make sense to me as I had always thought that the heavier the object is, the less likely it is to move.

So I bought some Federal 9mm 150gr. HST "Micro Pistol" ammo to carry in my Taurus 905. This is the heaviest commercially produced 9mm that I could find and Federal claims it is designed for short barreled 9mm pistols so it seems this load would excel in a snubbie.

Am I wrong in my thinking? Should I be choosing something more on the lighter end of the spectrum for 9mm in a snubbie?
 
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Not sure a definitive answer can be given.

I've heard of bullet jump involving the Ruger polymer revolvers.

Variances in manufacture probably play a big part.

By that I mean how well the taper crimp is.

I see in perusing 9 mm ammo that Hornady offers a Critical Defense
load with 9 mm bullet that has a cannelure.

That indicates, I think. that a bit of a roll crimp might be employed,
giving a tighter hold on the bullet than simply a taper crimp.

But that's just my idea or theory.
 
Not sure a definitive answer can be given.

I've heard of bullet jump involving the Ruger polymer revolvers.

Variances in manufacture probably play a big part.

By that I mean how well the taper crimp is.

I see in perusing 9 mm ammo that Hornady offers a Critical Defense
load with 9 mm bullet that has a cannelure.

That indicates, I think. that a bit of a roll crimp might be employed,
giving a tighter hold on the bullet than simply a taper crimp.

But that's just my idea or theory.
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My gun is a Taurus 905 with a full steel frame.

So the way the gun or ammo is made may play a bigger role then the actual weight of the projectile?

I'm just trying to get an idea of what 9mm ammo would work best for my snubbie.
 
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Just shoot the thing and see after several rounds if the rest have moved or not.

Personally, if you have these concerns I suggest you reconsider going to a
.38 with plus Ps and be done with it.

You've already planted enough doubt in your own mind to just forget about it.

A friend of mine has a 9 mm snubbie and complains that the blast/roar
of the 9 mm is disconcerting. He's giving up on it.
 
I currently own a Ruger Speed Six and a S&W 940 in 9mm and have not had any problems with bullet jump. I was using Speer Gold Dot 124grn in both for carry and Winchester white box for practice and had no problems with bullet jumping crimp. I did have the Taurus 905 but got rid of it but not because of ammo problems. Just go to the range and give it a try and find what works for your gun, the Taurus was nice because the gun/cylinder was made for the 9mm rather than a 38 converted. If I recall the Taurus was a bit snappy so be sure to have a good grip.
 
I've heard of bullet jump involving the Ruger polymer revolvers.
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I was surprised yesterday when I shot the hot Buffalo Bore out of my 17 oz LCR without any bullet jump. I shot two, measured for change in cartidge length (none) and shot two more. You would think that 617 ft. pounds ME out of a 17 oz would cause jump if it's going to happen! It is a roll crimp, though.
 
As UncleEd stated, measure OAL of the rounds using a caliper, shoot 2 rounds, remove moon clip and measure OAl of the remaining rounds. Shoot 2 more rounds, remove moon clip and measure OAl of the remaining rounds.
OAL, (over all length)
I shoot 45 acp revolver and the rounds are a tapper crimp and experience no bullet creep ( my reloads)
I also shoot a 627 using 38 short colt and use a tapper crimp and experience no bullet creep (my reloads)
 
Like I mentioned in your post over at the S&W forum - There are more variables to ammo than just weight of the bullet.

Typically this is not a problem with factory ammo. No one can answer your question because there is not enough data to answer your question. Any answer given will be a guess. If you look at the physics of it the heavier bullet would probably be more likely to jump crimp. Objects at rest tend stay at rest and a heavier bullet will be more likely to remain in the same position while the case recoils back along with the moonclips and gun. However larger bullets will also have more bullet in the case holding them in place so it's probably a moot point...

Problems occur with reloads due to variations in neck tension, bullet diameter, reloading die tolerances, reloading dies not setup correctly, etc. These are hopefully not an issue with the factory ammo being bought.

If you shoot a bunch of your loads and don't have a problem I wouldn't worry about it.
 
Is the cylinder short enough to allow this to happen? I'd think the bullet would be completely out of the case in order to hang past the front of the cylinder, but I haven't measured anything.
 
I have close to 2,000 rounds shot thru my Taurus 905, and have used many different weights, and types of ammo. I HAVE NEVER had an issue with crimp jump. Its one of the heavier 9mm revolvers, so I doubt you will have much of an issue.
 
weblance said:
I have close to 2,000 rounds shot thru my Taurus 905, and have used many different weights, and types of ammo. I HAVE NEVER had an issue with crimp jump. Its one of the heavier 9mm revolvers, so I doubt you will have much of an issue.
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The issue is more pronounced in lighter revolvers because they recoil more and with heavier bullets because they have more inertia and want to stay still while the gun and the rest of the cartridge are moving backwards.
 
I asked this on two other forums and surprisingly, only one person was able to give me a straight answer. He said that the lighter bullets would be less likely to loosen because they have less inertia. Huh? This doesn't seem to make sense to me as I had always thought that the heavier the object is, the less likely it is to move.
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This is correct. Less LIKELY.

Revolvers ARE kinetic bullet pullers!! Make no mistake about that. They just happen to use the opposite direction than the hammer type bullet puller we use in reloading.

Case rims (in 9mm the case held by the moonclip) are held firmly in place at the back of the cylinder. They cannot move forward, so when fired, the gun, and the case recoil back away from the bullet. It is the bullet's inertia that "pulls" the bullet, by keeping it in place (tend to remain at rest).

The heavier the bullet, and the lighter the gun (more recoil movement) the more likely this is to happen.

This is why revolver ammo is roll crimped. No crimp, just proper case neck tension on the bullet can work, in the right situation. Taper crimp can work, in the right situation. Roll crimp works in nearly every situation.

I expect the factory 9mm crimp to be adequate, except possibly in an ultra light revolver. Its an easy thing to check. Load it up and shoot all but one round, and then check that round for length. If it's longer than it should be, you have crimp jump.

Now, does that matter???? If its only fractions of an inch on the very last round, I'd say not.
 
"This is correct. Less LIKELY.

Revolvers ARE kinetic bullet pullers!! Make no mistake about that. They just happen to use the opposite direction than the hammer type bullet puller we use in reloading.

Case rims (in 9mm the case held by the moonclip) are held firmly in place at the back of the cylinder. They cannot move forward, so when fired, the gun, and the case recoil back away from the bullet. It is the bullet's inertia that "pulls" the bullet, by keeping it in place (tend to remain at rest).

The heavier the bullet, and the lighter the gun (more recoil movement) the more likely this is to happen.

This is why revolver ammo is roll crimped. No crimp, just proper case neck tension on the bullet can work, in the right situation. Taper crimp can work, in the right situation. Roll crimp works in nearly every situation.

I expect the factory 9mm crimp to be adequate, except possibly in an ultra light revolver. Its an easy thing to check. Load it up and shoot all but one round, and then check that round for length. If it's longer than it should be, you have crimp jump.

Now, does that matter???? If its only fractions of an inch on the very last round, I'd say not."

So what I can determine to be truth here is:

1. Light revolvers + heavy bullets in 9mm = more likely to crimp jump.

2. Heavy revolvers + light bullets in 9mm = less likely to crimp jump.

Thanks, this was the answer that I was looking for. I will choose my 9mm ammo on the lighter end of the spectrum.
 
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Inertia holds a bullet in place and the yank of the rearward recoil jerks on the casing.

Why isn't this a problem with semiautomatic weapons? Because your ammo is fully supported by your palm, ad with a revolver, the cylinder is flipped up and back.

There are only three factors that matter with ammo.

First, the heaviest bullets are most likely to stay in place through inertia during recoil, they will cause the greatest amount of stress at the friction point and are more likely to pull.

Higher recoil rounds will pull harder on the casing, pulling it away from the bullet with more force.

Acceleration during recoil may be the most important. The very hard, fast snap of heavy recoil rounds in a lightweight revolver is far more likely to break the friction and allow the bullet to pull.

No, there is no way possible to decide which rounds will pull just by thinking about it. You can learn by testing. No other way. Every brand number and lot have differences. See which weights and velocity rounds seem to have the hardest, sharpest recoil and don't use them, right? Use ones that seem to "hurt" less, because what you feel at the back, the bullets up front feel it too, as a jerk.

Regardless of all other factors, the lighter bullet will withstand the jolt better because of their lessened resistance to the yank.

Hornady does use crimp grooves. You can get Inexpensive fifty packs of xtp that are good defensive rounds. Test a box. Mark three rounds buy smearing ink all around where bullet meets case. put them in the cylinder and leave them there while you shoot the other three repeatedly. fire as many rounds as you can through the pistol, and visually check each time by looking for a bright spot in the ink.

Can you run twenty rounds through your pistol with no significant brass being exposed? If so, it is almost certain that your bullets will never pull.

The risk of one round pulling if it is exposed to a few recoil events has to be almost astronomically low. It is probably greatly exaggerated like an urban myth warning about getting stink bugs up your nose if you nap under a tree.

It is unbelievable that none of the ammo makers has released a special round, a revolver defense round. Optimal bullet weight and charge with a high friction fit. They can do the testing, thousands of people will buy them. Probably won't sell in many stores, but would do well online.
 
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i have the ruger lcr 9mm, i had slight movement with 115 grain freedom ammo but not enough to bind a gun up. the 124, 135 and 147 did not move or not enough i could tell eye balling them. i have been told aluminum ammo is a no no, also some guys testing have ruled out ammo in a way that i think is unfair, they will fire four and leave the 5th then reload 4 and keep shooting finally the 5th one comes out. if it don't come out or move a lot after 4 i'm good as i will shoot all 5 anyways.
 
It is unbelievable that none of the ammo makers has released a special round, a revolver defense round.
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At one time there was a 9mm Federal Rimmed Cartridge, introduced in 1989 for the Charter Arms revolver. I had a box once. Might still have it somewhere. 115 grain Jhp. Rimmed case. Hasn't been made in years.
 
Concerned Citizen wrote:
I always wanted a snubnose revolver that can shoot 9mm so I recently bought one.
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Congratulations.

I've heard about some cases where a 9mm bullet has loosened forward from it's case from the force of recoil out of a revolver and locking up the cylinder,
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This can happen with any revolver. It is not unique to 9mm.

It is a phenomenon governed by the inertia of the bullet (i.e. the inertia causes the bullet to want to stay put as the gun recoils backward) so the heavier the bullet, the more likely it is to happen - all other conditions being equal.

I asked this on two other forums and surprisingly, only one person was able to give me a straight answer. He said that the lighter bullets would be less likely to loosen because they have less inertia. Huh? This doesn't seem to make sense to me as I had always thought that the heavier the object is, the less likely it is to move.
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Congratulations to the guy who mentioned inertia.

It will make sense when you turn your frame of reference to the bullet. You are correct, the heavier object is less likely to move. That means the bullet tends to stay in place while the rest of the gun moves rearward in recoil. We talk of the bullet moving forward, but the reality is that the gun (and the cartridge case) is moving backward faster than the bullet, so the bullet appears to be moving forward.

Am I wrong in my thinking? Should I be choosing something more on the lighter end of the spectrum for 9mm in a snubbie?
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It's unlikely any bullet will walk out.

You have to decide what self-defense situation you are likely to be involved in and whether in that most likely of scenarios you are better off with more velocity or more mass.

You will inevitably get all sorts of answers, but the fact of the matter is the human body is not a block of ballistic gelatin and your effectiveness is going to vary based on whether the bullet hits bone, muscle, vital organs, or spends most of its journey passing through the pleural space.
 
You can't make a decision based on bullet weight alone.

I have an LCR 9mm, and in looking on the net i've found lists of rounds that others have tested and found good.

Best to pick a couple types of practice ammo and SD ammo, test them yourselr in your own gun, and then stick to the ones that work.

It's not as big a deal as some think as most reputable factory rounds will work fine. But you should test them yourself.
 
Hornady is my go to defensive load with my 9mm 642-1... one of the better crimp companies. I prefer 147 grain, standard pressure.

For range ammo, had good results with UMC bulk.

All you need to do is load up a moonclip, shoot four, and see what the last round looks like. People try to do multiple cylinders, realistically... worry about four rounds. You aren't going to reload a moonclip in a defensive situation, so at worst, you'll reload that single round on the moonclip.

I've been dealing with a few different methods to carry reloads, and likely going to do a thread on what I have... and what works and doesn't. Want to get it done sometime this upcoming month...
 
Hornady does use crimp grooves. You can get Inexpensive fifty packs of xtp that are good defensive rounds. Test a box. Mark three rounds buy smearing ink all around where bullet meets case. put them in the cylinder and leave them there while you shoot the other three repeatedly. fire as many rounds as you can through the pistol, and visually check each time by looking for a bright spot in the ink.
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Thanks for all the helpful info form everyone, your post was probably the most helpful.

Does Hornady use crimp grooves for 9mm in their Critical Defense/Critical Duty line as well as XTP?
 
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