9mm bullet with a crimp groove for revolver?

[nevadabob]

Not a cannulare but an actual crimp groove as some 38 specials have. I'm trying to find the best bullet for my CA 9mm Pitbull revolver. My standard 9mm loads (125 grain) all have a tendency to jump crimp. If I crimp too much I get accuracy/keyhole problems. And not enough crimp the bullet walks. I'm a casual plinker and target shooter. I feel an actual groove with a slight roll crimp would suffice. Is there a mould for such?

[gpidaho]

Measure the throats and size any bullet of thirty five caliber to fit. Moulds for tumble lubed bullets have small lube grooves that can be used as a crimp grooves. Gp

[mdi]

One of my best mold designs is my Lee 125 gr. RNFP. I use it in 3, 9mm pistols and 3, 38 Specials and one 357, just sized to fit whichever gun it will be used in. For the pistols I ignore the crimp groove and the revolvers get a roll crimp.

[Outpost75]

Accurate has several, 36-142H shoots to the sights of my S&W 942. 35-120H is another possibility if you want a lighter bullet.

With either you can order different diameter as needed for your gun and alloy.

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[crackers]

That idea can lead to a loss of headspacing on the mouth and really hammer the extractor tabs. I tolerate a bit of movement in an LCR with no big effect. Four shots won't lead to the fifth anywhere near pulling free.

[Outpost75]

That idea can lead to a loss of headspacing on the mouth and really hammer the extractor tabs. I tolerate a bit of movement in an LCR with no big effect. Four shots won't lead to the fifth anywhere near pulling free.

In my S&W 940 9mm ammo headspaces on the clip. The revolver chambers are deep enough to accept .38 S&W and I can shoot .38 S&W ammo without clips or 9mm with clips.

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[nevadabob]

I appreciate the responses!

[Jack Stanley]

Just an idea , would a taper crimp help with your current bullets ??

Jack

[reddog81]

I’d start by tweaking your current dies to see if you can get better neck tension. How would you roll crimp a 9mm case?

Any appropriate 115 to 147 bullets for .38 Special will work in 9mm. I’ve used many piles of a .357 sized 160 WFN in my S&W 929, however I don’t use the crimp groove.

[jsizemore]

This should work since there is enough body diameter forward of the crimp groove to give you a taper crimp for 9mm:

http://accuratemolds.com/bullet_detail.php?bullet=36-110C-D.png

Tom can give you a smaller diameter bullet tailored to your specs. It's got a bit of bevel base to fit the 9mm internal case taper to seat a little deeper for the crimp at the case mouth.

[nevadabob]

I've been offline since our pc had to go the tech repair shop. Doing this on a borrowed notebook. I ordered and received a sample pack of Falcoat 38 tcfp 125 gr coated bullets (358's) that look like what jsizemore recommended. I don't do any casting but have an interest. I went ahead and loaded some and will post a pic today.

[nevadabob]

Here's my bullet pics. They are actually Ringers 125 gr coated (358's) TCFP 38's:

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Looks very close to a roll crimp. Now I need to go out shooting and chrono these and measure for bullet jump. The crimp is right on the crimp groove. I slugged my barrel and it comes out to 356-357.

[wv109323]

I would increase my bullet diameter by .001 or .002" to increase my neck tension. I am not sure if you are using moon clips but if the case headspaces on the case mouth a roll crimp would change headspace which may hurt your primer ignition.
I tried to load some 9mm shot shells with a heavy roll crimp and they would not fire in an auto.

[RED BEAR]

Why not just use a bullet for 38 spec i shoot them all the time in my 9 mm. If you know they are going for 9 mm then just size according. There is only a couple thousands anyway. A lee 105 swc works great but any but the heavies will work.

[mozeppa]

why make a fish lay duck eggs?

use 9mm in a 9mm gun ....use 38 special in a 38 special gun!:veryconfu

[crackers]

"Looks very close to a roll crimp."

When the firing pin hits the primer, what stops the forward movement of the case?

[SvenLindquist]

9mms w/o moon clips headspace on the case front. A good taper crimp will work just fine.

If they don't come apart in a 30 round Glock full auto double stack magazine, they won't in a revolver.

[nevadabob]

My 9mm revolver is Charter Arms which has special installed "clips" on the cylinder to hold the case in place. No moon clips needed.

Jack Stanley - My 9mm bullets tend to jump crimp when shot thru my revolver. See my initial post.

reddog81 - That's my problem: tweaked and retweaked the crimp on my current 9's all to no avail. That's why I'm jumping ship to try 38's simply because of the crimp groove.

wv109323 - If successful, the 38 loads will only be for my revolver. By success I mean accurate (10-12 yards), no keyholing, and minimal crimp jump on round #5. By minimal I'd be happy with less than .005" jump.

Red Bear - Got it!

mozeppa - Agree...but see my initial post.

crackers - see my comments above in this post.

Sven - If my taper crimp was sufficient to prevent crimp jump I wouldn't have started this thread! Not being smart-Aleckey! Auto's can suffer from bullet setback and not crimp jump.

Moral to the story: We've had much snow and even more rain here in Reno NV. My shooting spot is about 30 minutes away and the dirt road is a mess! When conditions permit I'll assess these 38 spcl bullets in my 9mm cases and report back.
I appreciate all who have responded!

[winelover]

Personally, I wouldn't roll crimp a 9mm cartridge. Why manufacture ammo that can only be used in a revolver? I'm guessing, like me, most reading this thread...............also own a autoloader chambered in 9mm.

On the other hand, just because a bullet has a crimp groove, you don't have to use it. Most of the time a bullet designed with a crimp groove....................like ones designed for 38/357, the crimp groove probably won't line up for the COAL your gun needs, anyways. COAL's are especially critical in small capacity cases, due to very fast increases in pressures.

Winelover

[Lloyd Smale]

try a Hornady crimp taper crimp die or a lee factory crimp die. It should hold any bullet without the need for a crimp grove. Like red bear said. You could use any 100-130 grain 38 bullet without troubles using moon clips. The 105 lee is surprisingly accurate in most of my 9mm guns and you don't even have to worry about running a slide or feeding.

[RED BEAR]

Exactly what makes a bullet a 9 mm or a 38 spec ? They are both almost the same size lyman makes molds they list for either caliber the devastater hollow point mold for instance. I know a lot of people who use the lee 105 gr swc in 380 or 9mm. But you're welcome to use what you want i just don't see limiting your self.

[nevadabob]

Winelover - And COAL can be a very subjective thing. For powder purposes, it all depends upon the length of the bullet and where one crimps. For my above rounds, on a pulled bullet, the measurement from actual crimp line/ring to the bullet base is almost identical to a pulled standard 9mm bullet. So the real issue, as far as case powder/compression goes, is how much of the bullet occupies the case. With my revolver, what protrudes from the case is a non-issue. Now if we were talking semi's, COAL is very crucial to the PLUNK test.

I just came across this website that sells coated 38's that offers this bullet. Note the different offerings in bullet diameter:

https://bangandclangllc.com/products/125-grain-38-357-and-9mm-tcfp-fb-sized-0-356-0-358-coated.html

[nevadabob]

Lloyd & Red Bear - Yes and thanks!

[SvenLindquist]

"Sven - If my taper crimp was sufficient to prevent crimp jump I wouldn't have started this thread! Not being smart-Aleckey! Auto's can suffer from bullet setback and not crimp jump."

My experience is different, I have never has a properly done taper crimp lose a boolit in either direction. Not in a 10mm, 45 ACP/AutoRim or 450 BM.

You may want to review your die's instructions and measure the crimped case mouth vs specs for a proper crimp.

Found this on the net:

"Listening to reloading talk at the gun club, you'd think that crimp is part voodoo, part rocket science. How much, and how much for which caliber and application, seems as much random guesswork as it is recordable, testable mechanics.

Crimp, in this context, is the pressing of the case mouth back into place after seating the bullet—the final step in reloading your own ammo (well, the last step before inspecting said ammo). And to compound it, we have two crimps: roll and taper. Generally speaking, roll crimp goes on revolver rounds, and taper goes on pistol, but taper is so versatile it can work on both.

Taper crimp is much more forgiving than roll crimp, but it is also more subtle, so this article will delve into the aspects of taper crimp.

Your taper crimp die has a short section of cone-shaped taper at the top. You adjust how much crimp you are applying by screwing your die deeper into the press.


When you press the loaded cartridge in—you really should seat the bullet and taper-crimp as separate operations, not do both in the same die—the tapered portion squeezes the case mouth in. But it crimps it in as a cone, it constricts it evenly, and it keeps the case mouth pointed forward, not turning it inward—as the roll crimp does.

You want to do enough but not too much. If you crimp too little, the extra drag of the un-crimped mouth will cause feeding problems. If you crimp too much, you'll get a round that won't chamber or won't shoot accurately.

I have a sample that was over-crimped into a jacketed .45 ACP 230-grain roundnose, and when the case couldn't be crimped any more (the hard bullet stopped inward progress) the case then buckled. To no one's surprise, the reloader complained of unreliable function in his pistol. An over-crimped lead or plated bullet tells you it is unhappy by hurling patterns, not groups.



For taper crimp, practical shooting reloaders have been doing it long enough to have hard measurements. Take the bullet diameter, plus twice the case wall thickness and then subtract .004 inch. As a general rule, and rough estimate, you can count on a handgun case wall being right around .0001-inch thick. So for the .45 ACP, take a bullet of .452 inch, add .010 inch twice for a total of .472 inch. Then subtract .004 from that .472 and you get a goal crimp of .468 inch. Apply the same arithmetic for other calibers. A .40 or 10mm would be .400 plus .020 minus .004, which leaves us at .416.

Take your caliper and measure the diameter of a loaded round right at the case mouth. The number you get should match the calculation. (And while it's a less precise telltale sign, if you rub your fingertip down a case and feel a right-angle edge around the case mouth, the round is insufficiently crimped.)

Since many pistol bullets lack a crimp groove or cannelure, you'll be taper-crimping into the bullet itself. If you taper-crimp a revolver cartridge (yes, it works; I do it for almost all my revolver rounds) you have it easier. Since you'll have a crimp groove or cannelure in your revolver bullet, you can start with the calculation but crimp into the groove. If you want, crimp a bit more, until the edge of the case mouth contacts the bottom of the crimp groove or cannelure.

Now, not all bullets, nor all cartridges, are happy with this measurement method. If you find accuracy goes all to hell with the calculated crimp, you will have to experiment.

I have found the 9mm to be particularly touchy in this regard, especially with plated bullets. Minor variations in your particular set of dies, your press and your handguns (not to mention the brand of bullets you are using) may require small adjustments in order to produce the best results. But the above method will get you in the ballpark.

When you are setting up your press, it is best to start with a vanilla-plain load, with known performance, and load only a few rounds in each of two or three taper-crimp settings. Record where the die and lockdown rings are for each, and then check your new ammo on target.

Revolvers are spectacularly forgiving of casual taper crimp into the crimp groove, until you get up to the hottest magnum. And then they might get touchy.

Okay, what don't we use crimp for? Bullet security, a job best handled via neck tension. While the crimp does a small part to control set-back and bullet pull, the main work in that area is done by the neck tension.

You control these factors by the diameter of the neck expander in your die set. A neck that is too large to control set-back or bullet pull cannot be corrected with crimp, no matter how ferociously you crimp the case. All you do is hasten the onset of neck splits.

As an aside, you have correct neck tension when you can see the "Coke bottle" effect on your case, once loaded. If the case tapers inwards beneath the base of the bullet, like the bottom half of an old-school Coke bottle, then you have a good amount.

One good crimp/neck-tension check to perform is to load a couple dozen rounds, measure the overall length of one round, mark it and place that one at the bottom of a magazine. Shoot the magazine, except for the last round. Eject it and measure it. Has it become shorter? If not, good. Load it at the bottom of another magazine, shoot all but the marked round, eject and measure it. If it's still the same length and accuracy is good, you're done.

If it shortens due to recoil, start over with greater neck tension. Load another 10 to 12 rounds and try again. It can take a bit of fussing, but the results are worth it."

[nevadabob]

Thanks Sven! My revolver is a 2" snubbie which makes it more likely to jump crimp and be fussy.

[jmort]

If you have a 9mm revolver, especially the LCRs, and I do, then you know that bullets jumping crimp is a problem, the kind of problem that can be fatal. A crimp groove or cannelure would be helpful.

[tazman]

I have a S&W 929. It uses moon clips to hold the cartridges in place. The chambers in the cylinder do not have a ledge for the case mouth to headspace against. It is all controlled by the moon clip.
I have yet to have a boolit jump the crimp that I am aware of. I say it that way because the cylinder is much longer than the OAL and the boolit would probably need to come completely out of the case for it to jam the cylinder. This has never happened to me.
Of course, this revolver is substantially heavier than the smaller revolvers like the LCR and has much less felt recoil.

[crackers]

"...has special installed "clips" on the cylinder to hold the case in place."

No, those tabs are relatively fragile and intended to push out the fired cases - not resist hammer impact. Your next problems will be poor ignition and leading.
Charter will likely fix your extractor for free, but that's how reloaders continue to suffer a black eye.