Crimp Question

[robhic]

First post and let me just say that I am very new to reloading. Reading a lot (books and manuals) and I think I have a decent grasp. Also a compliment - when Googling for information about some things this forum came up in almost 8 of 10 responses which is a primary reason I joined The Firing Line.

OK, enough kissing up , I have a quick question that I'm hoping doesn't end up being a "Duh!" moment. All I've read says the straight walled cases like 9mm and .45acp use a taper crimp. I am using jacketed bullets mostly for range use (for now). So far so good, but I am using the RCBS "Rock Chucker" SS press and want to try some .38spl and the 357 magnum which work in the same die.

These two rounds call for (especially the 357) a roll crimp. The jacketed bullets have no canellure. Am I 1) missing something, 2) gonna have to do something special for jacketed bullets that have no canellure or 3) find different bullets (which I haven't seen) other than lead?

Thanks to anyone who can demystify this for me and help me figure out how I can roll crimp a bullet that seems to have no provision for one. Or does it not need it? I don't have lead bullets at this time....

[Unclenick]

Welcome to the forum.

What bullet are you using? All the Hornady and Sierra and Speer jacketed bullets of .357" diameter have crimp cannelures. Plated bullets are another matter, but they are soft enough you can force a crimp into them. If you got .355" 9 mm bullets by mistake, some of those don't have crimp cannelures, but they aren't the right size and so may not shoot well anyway (depends on your revolver's dimensions).

Understand that roll crimping was once all there was. Self-loading Pistol shooters would mostly just use very light crimps that took the expander flare out of the case. Taper crimping was developed to do that plus avoid working the edge of the case mouth as much, so the case mouths would withstand more reloading cycles before they started to split. The taper crimp ledt the case mouth a better shape to headspace on and still prevented recoil from driving the bullets back into the cases by banging the magazine against their noses or by giving them a hard shove against the feed ramp during loading.

For revolver, you roll crimp to prevent bullets coming out inside the chambers that haven't been fired yet. When a revolver recoils, it pushes backward on the rims of the cases via the cylinder, and this acts like an inertial bullet puller in reverse. That is, it pulls the case off the bullet, whose inertia tries to keep it in place. However, keep in mind this problem is biggest when the recoil is sharpest. So, a heavy gun firing a light load may not need a roll crimp at all. I shot lots of taper crimped .38's and .357 wadcutter loads in my K-frame Smith and my Dan Wesson without any problem. The recoil just wasn't sharp enough to pull bullets. At the other extreme, a friend of mine has a lightweight titanium revolver in .45 Colt that cannot be used with the standard 250 grain bullets. Even new commercial rounds all pull the bullets in that gun with its stiff recoil. He has to go to 200 grain bullets before any crimp he makes will stop that from happening.

Anyway, to know whether or not you need a roll crimp you may have to experiment. Load two rounds with one empty chamber between them and so the round you will not fire is on the opening side of the cylinder or under the loading port (for single action revolvers) when you fire the other one. Measure the length of the bullet you won't fire. Fire one, then remove the other and see if you can measure it having lengthened any? If so, you need more crimp. If not, repeat several times, keeping that same round unfired to see if multiple recoil events back the bullet out any. If not, you are good to go with whatever crimp you used. If it does back out, you need more crimp to prevent a bullet backing out to the point it jams rotation of your cylinder.

[mikld]

This seems to be one of the problems common to new reloaders using plated bullets. I would try and find a taper crimp die for the calibers you want to reload and crimp the same as a semi-auto round and follow Unclenick's method to make sure bullets stay in place during recoil. Some lightly crimp plated bullets for revolver use with a roll crimp, but need to be careful not to cut through the plating (inaccuracy, leading).

Normally I tell new reloaders to find a tried and true load (components and charges) in their reloading manual, then buy components. In the case of a .38 Special, a 158 gr. bullet with crimp groove or cannalure, loaded over a powder in the W231/HP38 range. This combination has been reloaded prolly 1.59 bizillion times and all the problems have been worked out and reported on...

[Unclenick]

It's important to mention, by the way, that plated bullets, like Berry's or Ranier or others, are not the same as jacketed bullets. They are softer. The maker may recommend you stick to lead bullet loads with them or not load past the middle of the jacketed bullet range.

[T. O'Heir]

Hi. Unless you're loading hot(or for a lever action rifle), neither .38 nor .357 really need a crimp. However, when they do, you use as little crimp as possible. Just enough to hold the bullet in place under recoil.
Your regular .38/.357 seating die will have a roll crimp in it already. Just adjust it down a bit at a time until you put enough crimp on. Jacketed bullets without a groove can still be crimped doing this.
"...enough kissing up..." Faster to send money or beer(not that stuff made with rice in it that's filtered through a great big horse though.) snicker.

[TheGuyOfSouthamerica]

I say the same as Unclenick and OHeir.

For pistols you need an taper crimp since the head space has to be correct. I have an Hornady Taper crimp 2 3die set for 9mm Luger and the same taper crimp 3 die set I ordered for the 380 acp I plan to buy (Beretta Pico). I cast my own bullets.

For revolvers I use allway an taper crimp set as well (RCBS 3 die set series B I believe. 38spl/357 mag). No problem whatsoever. I cast my own bullets. I recommend ONLY taper crimp.

In both cases I about undue only the case mouth belling with the crimp.
As I understand roll crimp has to go exactly into the cannelure which may be an hassle since with repeated reloads I realised the cases shrink instead of expand. So trouble may be ahead roll crimping in that case. Taper crimp you seat them were it goes an you are fine if you stay midway below max powder charge. Taper crimp is easier and more foolproof.
If you measure the cases you will notice about no one is the same length. They can vary considerably in legth even if the are fired only once.

[robhic]

I'm gonna address this to Uncle Nick (since his post was first) but thanks to all who replied.

Thanks for the welcome and I already have to admit a mistake. I said jacketed bullets but I should have said RAINER PLATED BULLETS. There's the first DUH! moment. And they are .357 dia., 125gr for 38/357 use. I'm loading down at the starting level for now and will work up after getting more comfortable with this whole thing. I just had read that (like you stated) the 357 could poke out from recoil forces and jam the cylinder.

I am using a 2" snubbie so an overly powerful load isn't my idea of fun. Shooting RN for range duty until I get better and then maybe some HP and a bit hotter load (not a lot) to follow. So, if I'm reading this right, it looks like a taper crimp - like I'm using on my 9mm and 45acp loads - will be all right. I DO plan to use that two alternating loads test you mention to see if OAL changes. Never saw that before, thanks for the tip!

So again, thanks to all and this might not be as complicated as I expected making the roll crimp. I appreciate all the info and your time!

[44 AMP]

It's not terribly complicated, but crimping is probably the easiest part of reloading to screw up without trying.

There are certain steps that you must do right, or your results will be ..suboptimal.

A good taper crimp can work in revolvers, a good roll crimp always works.

If you measure the cases you will notice about no one is the same length. They can vary considerably in legth even if the are fired only once.

This is why they make case trimmers. Unless you want to do each round individually adjusting the die for each round, trimming them so all in the batch are uniform length is needed.

Several good points have already been mentioned, so I'll skip them and just say that plated bullets are what you got, and can be used, but when they're gone, you might consider just lead, and jacketed for some loads. Bullets MADE for revolver use, with a cannelure or groove for roll crimping.

[noylj]

Why not save them for 9mm and get the right bullets?
For ANY roll crimp job, get a Redding Profile Crimp Die.
You can roll into the plating, but you can also cut through the plating and have problems.
One trick that has been done for over 100 years is to seat the bullet deep enough that you can just roll crimp over the bullet ogive. Round will look slightly weird, but they won't back out of the case and lock up a cylinder.
Otherwise, simply taper crimp them and check the last two rounds in each cylinder full to see if the bullets are creeping out of the case.

[robhic]

44 AMP "Several good points have already been mentioned, so I'll skip them and just say that plated bullets are what you got, and can be used, but when they're gone, you might consider just lead, and jacketed for some loads. Bullets MADE for revolver use, with a cannelure or groove for roll crimping."

That thought crossed my mind along with getting a trimmer. Since these bullets are, more-or-less, fancy lead it seems that from what's already been posted (above) a good taper crimp should be OK with the .38 and probably OK with the 357. By the time I use the 100 or so bullets I bought for these 2 calibers, I'll be feeling comfortable enough to work up some hotter-than-range use loads. Then I'll get some gooder boolits w/cannelure and roll crimp (I already studied the instructions with the die set). Just a note: these bullets were sold/marked for 38/357 use at the Midway site where I got 'em.

noylj: I don't think bullets of .357" dia. would work well in 9mm so that thought never crossed my mind. With the fact that they're marked for 38/357 use and I'm only starting and will use them for range use for now, I'm gonna stick with taper crimping and the "shock test" Uncle Nick gave me in his post. Next time, I'll get more appropriate bullets and get a bit more sophisticated in my revolver load making. I don't shoot 'em that much, anyway....

Thanks, again, to all for the time and information/tips. I appreciate it!

[mikld]

An aside/hitch hike and FWIW; I have a load for my house gun (2" 38) that consists of a 150 gr. DEWC over a stout load of W231. I believe it would deliver much tissue damage from the flat end and not "over penetrate" keeping the neighbors safe. I shoot this load often and it's not unpleasant to shoot in my "little gun". Jes a thought...

[TheGuyOfSouthamerica]

I have as well an Wadcutter in my 357 mag SAA Revolver (5.5" Barrel). I load them "Nagant style" deep (~0.113" deeper from flush). I use 3.4 grain Vectan A1 (same as VV N340) behind an Lee 148 grain (Elmer Keith style grease grooves) Wadcutter.

I shot them today as an comparison with my 9mm FMJ Relaods and they penetrate as deep as did my FMJ 9mm Lugers from 40 meters. Primers look normal (a Little flat but OK) and no bulges in the cases nor sticky cases.

The Wadcutter IMHO is a nice crushing bullet which makes an full caliber hole.

Those Wadcutters I just undue the case mouth belling with the crimp. That is because the WC is seated so deep, the case itself (since it is resized from the first die) holds the bullet very firm (often those cases Show slight bulge were the round is so you can feel were it starts and Ends in the case when loaded) and I believe it may have engaged the case tapering already (tapering from inside).

This bulge in the case may be normal according to Lymans 44th Reloading Manual as it addresses the issue for the 380 acp (see below)

{Edit: Posting of copyrighted material without permission of the copyright holder is not permitted on the board. Please read the board rules on posting copyrighted material.}

I never resize the cast bullet at all. I use them "as cast".

[Dufus]

noylj: I don't think bullets of .357" dia. would work well in 9mm so that thought never crossed my mind.

I size my cast bullets to 0.357" for use in all my 9s. They have to be over bore to shoot right in ANY gun, rifle or handgun.

[Mauser69]

My apologies if this was covered above, but I did not see it (Tried to read all the replies, but must admit to skimming some due to being somewhat bored with the subject).

Anyway, as a new reloader you need to understand the differences in the crimp types. Several folks have already mentioned that this is not specific to just "straight walled cases", but is more appropriately associated with the GUN and the CALIBER. Rounds to be used in an auto-loading pistol use the taper crimp because those calibers head space on the case mouth (therefore the case mouth must remain proud of and square to the bullet surface, not rolled in).

But the part I did not see above is that the type of crimp your dies can make is GENERALLY controlled by the caliber - a crimping die only does one type, either taper or roll. The vast majority of REVOLVER caliber dies (such as .38/.357) all come with roll crimp dies, no matter what brand you buy. If you want to taper crimp those calibers, you have to specifically find the much less common taper crimp dies.

On the other hand, virtually all dies for PISTOL calibers (such as 9mm or .45ACP) come with taper crimp dies, no matter what the brand. Those calibers are designed to only head space on the case mouth, so even if you have a revolver that can shoot them (such as a Ruger convertible), these calibers STILL need to be taper crimped, not roll crimped.

With either type of crimp, you must know how to properly adjust your dies, and consistent roll crimps are more sensitive to consistent case lengths than taper crimps. Using the least amount of crimp that works reliably for your load is virtually always the best choice.

[robhic]

Mikld: I live in an all brick house, alone a bit isolated so penetration doesn't concern me. AND - yes (don't hate me!) I succumbed to the allure of the Taurus "Judge" for a bedside gun! Loaded with those evil-looking PDX1 shot-loads, I don't worry about anything between that and the wireless alarm system....

Dufus: Interesting point about cast 357 bullets working in 9mm guns. All the ones I have are .355" and plated/jacketed as I only shoot Glocks and they forbid under penalty of banishment using lead boolits in their guns. So as a good Glock fan-boy I don't shoot lead.

Mauser69: I'm using an RCBS "Rock Chucker" w/RCBS dies and the 38/357 die instructions (I read them a few times) tells how to make roll and taper crimp with the die set. I assumed I was OK to do either as I choose. After reading all the above info, I am gonna give the taper method a try with low-power loads for range use and the dummy round in the cylinder to see if it extends OAL after shooting the other rounds with only a taper crimp. If it don't woik, I guess I'll get boolits with a groove and practice roll-crimping....

Thanks again.

[jetinteriorguy]

For .38 special you can usually just remove the flair and be fine, or just lightly roll crimp. But for .357 mag the best thing is the Lee Collet Crimp die, it eliminates the inconsistency of a roll crimp on untrimmed brass and is very easy on the brass for increased life of the brass. But if you plan on shooting either caliber in a lever action rifle you need a good solid crimp.

[noylj]

<*noylj*: I don't think bullets of .357" dia. would work well in 9mm so that thought never crossed my mind. With the fact that they're marked for 38/357 use and I'm only starting and will use them for range use for now, I'm gonna stick with taper crimping and the "shock test" Uncle Nick gave me in his post. Next time, I'll get more appropriate bullets and get a bit more sophisticated in my revolver load making. I don't shoot 'em that much, anyway....

They work great in 9x19. At one time, there were NO 0.355" bullets on shelves and everyone with a 9mm Luger used 0.357" jacketed and 0.358" lead bullets.

Just remember, without a roll crimp, you should check the last one or two rounds in a cylinder to be sure the bullets are not walking out of the case, at least for the first several cylinder's full. Better than having the cylinder locked up and looking for a gunsmith to open it for you.

[Mauser69]

Mauser69: I'm using an RCBS "Rock Chucker" w/RCBS dies and the 38/357 die instructions (I read them a few times) tells how to make roll and taper crimp with the die set. I assumed I was OK to do either as I choose. After reading all the above info, I am gonna give the taper method a try with low-power loads for range use and the dummy round in the cylinder to see if it extends OAL after shooting the other rounds with only a taper crimp. If it don't woik, I guess I'll get boolits with a groove and practice roll-crimping....

And this is EXACTLY why I added my response to this thread - as a new reloader, you have so much to learn - actually studying the text in a good loading manual like Lee or Lyman will teach you most of it, but you still do no know what you do not know!

The RCBS die instructions are GENERIC, for all their dies. But they DO contain a key piece of information to which you seem not to have paid attention: in the Taper Crimp section there is a clear "(Note: Taper crimp seater dies are marked "TC" or "Taper Crimp" for easy identification.)"

If you go to RCBS' web site you will easily find that 3-die carbide sets in Group B for popular pistol cartridges are clearly specified for either Roll crimp or Taper crimp. .38/.357 dies, part number 18212 are for ROLL CRIMP. Part number 18215 are for TAPER CRIMP. You CANNOT assume things in this hobby. You MUST follow the part of the instructions that are correct for the specific dies you have.

[robhic]

"And this is EXACTLY why I added my response to this thread - as a new reloader, you have so much to learn...

The RCBS die instructions are GENERIC, for all their dies. But they DO contain a key piece of information to which you seem not to have paid attention: in the Taper Crimp section there is a clear "(Note: Taper crimp seater dies are marked "TC" or "Taper Crimp" for easy identification.)"

If you go to RCBS' web site you will easily find that 3-die carbide sets in Group B for popular pistol cartridges are clearly specified for either Roll crimp or Taper crimp. .38/.357 dies, part number 18212 are for ROLL CRIMP. Part number 18215 are for TAPER CRIMP. You CANNOT assume things in this hobby. You MUST follow the part of the instructions that are correct for the specific dies you have."

I do appreciate your making these points. However I am now confused! I looked at my die-sets (carbide btw) because I had read that in the literature about the 'TC' marking (which mine don't have). I went to the RCBS website and looked at the sets and they do, indeed, make roll and taper crimp sets.

But I have the 18212 set so I can roll crimp if desired. I'll have to play around with this to see what I can/can't do with it.

Regardless, good information and thanks for following up and adding it!

[TheGuyOfSouthamerica]

robhic,

If you wanna partout roll crimp the just do it.

If you use lead bullets then it does not matter if you are not hitting all the time the crimping groove on the bullet. IMHO it makes not a difference.

It is just I taper crimp all for uniformity, longevity (till now I never had to throw away a case) and ease on all my calibers.

[44 AMP]

OK, re-read the thread, and would add a few comments to the fine advice already given.

Generally speaking, .38SPl/.357 Mag dies have a roll crimp in the seater die.

There are two reasons to crimp .38/.357 ammo, the "bullet puller" effect (crimp jump) that can happen in revolvers, and the second reason that doesn't apply to you, (yet ) to enhance combustion of slow powders in magnum loads.

.38/.357 is right on the edge where crimp jump is a concern. It very much depends on the level of recoil, and the size (weight) of the gun.
(assuming, of course, proper case neck tension on the bullet)
I can shoot mild uncrimped .38 loads from a S&W N frame without the bullets moving. Shooing the same ammo from a light .38 snub nose, and the bullet move a little. So I always put at least some crimp on all of them.

Uncle Nick's method of finding how much crimp you need

Load two rounds with one empty chamber between them ...

is a good start. When you can fire all the chambers (but one) and the bullet doesn't move in the unfired round, you are done.

The "quick and dirty" method I use for finding my starting point when setting crimp is a factory round.

Seat one (or more) of the bullets you are going to use to the correct depth.
then back the seating stem out of the way.

I screw the die in until the crimp shoulder firmly contacts the factory round (hand tight only, don't reef on it), screw the locking ring down to contact, as a reference, don't lock the die in the press at this point.

back the die off a little.

Using the earlier seated bullet, adjust (in SMALL changes) until you get the amount of crimp you want, (which may be before the lock ring bottoms out, or not, your case might be a little different length than the factory round, that's why I said, for reference), then when the amount of crimp is right, lock the die in, and run the seating stem down to the bullet, and you should be set to seat and crimp in one step.

Note that this only works when your cases are uniform in length. A case a few thousandths shorter than the one you set the die with won't get enough crimp, one a few thousandths longer could be buckled and might not chamber.

With light loads, and a LIGHT touch of crimp, your plated bullets should work ok, resisting crimp jump, even in a light snub nose.

Be a good Glockfanboy when shooting a Glock, but revolvers were designed for lead, and they like it! so don't overlook them in the future.

Good luck, and let us know how things work out.

[robhic]

The "quick and dirty" method I use for finding my starting point when setting crimp is a factory round.

Seat one (or more) of the bullets you are going to use to the correct depth.
then back the seating stem out of the way.

I screw the die in until the crimp shoulder firmly contacts the factory round (hand tight only, don't reef on it), screw the locking ring down to contact, as a reference, don't lock the die in the press at this point.

back the die off a little.

Yeah, I've used factory ammo previously and it seems to be a good way to start. I also plan on making and keeping dummy rounds of the right size(s) to use for same. First 38/357 will be lo-power until (and after the 'Uncle Nick Test) I use the plated bullets and buy more w/cannelure. I might actually figure this out! And thanks for the time and info. I'll be going slooooow to start on everything because I like having all 10 fingers intact....

[44 AMP]

Small steps, learn to walk before you run, etc.

We'll help any way we can, gladly.

Tip: when convenient, get a kinetic bullet puller (hammer type). I use the LYman orange one, when needed.

You will, at some point want it. When you screw up a round, and we ALL have done it, or will do it , the puller will let you recover at least some of the components.

I remember when I was just starting out, every case was important, and primers were precious like gold, bullets nearly so. Almost cried when I mangled a round because I didn't have things as right as I thought. (ok was a teenager mowing lawns for money, and I was ALSO CHEAP, but still, it hurt when I damaged components due to MY error.)

I learned a lot of what NOT to do, by trial and error. No internet in those days, just books and gun magazines. No organized group I could just talk to (24/7) with collective hundreds of years of experience...

You kids today are SOOO spoiled!

Good Luck, and when you figure out what to ask next, we'll be here to answer.

Some answers might even be right!

[robhic]

Tip: when convenient, get a kinetic bullet puller (hammer type). I use the LYman orange one, when needed.

You will, at some point want it. When you screw up a round, and we ALL have done it, or will do it , the puller will let you recover at least some of the components. You kids today are SOOO spoiled!

Got and used the bullet puller already. Yes, it was a good investment! Also got a case-trimmer for just in case. Would it shock you that I turned 63 in October? YOU kids jump to conclusions so quickly. Why, in my day.....

[44 AMP]

why, in my day, you were a kid starting out reloading, no matter how many winters you had seen. Not about chronological age, its about round count, and calibers loaded...

and we were loading for dinosaur, back then, hunted them up hill, both ways!


.22 Hornet, .221 Fireball, .222 Rem, .223 Rem, .22-250, .243 Win, 6mm Rem, .25-06, 6.5x55mm Swede, .30-30 Win, .30-40 Krag, 7.62x54R, .308 Win, .30-06, .300 Win Mag, .303 British, 7.7mm Jap, 8mm Mauser, .350 Rem Mag, .375 H&H, .45-70, and .458 Win Mag, .32acp, 9MM Luger, .38 Super, .38Spl, .357 Mag, .357AMP, .44Spl, .44Mag, .44AMP, .45acp, .45 Colt, & .45 Win Mag.

Semi autos, bolt guns, lever guns, and single shots. Single stage presses, turret press, progressive press, I've learned a few things about all these.

Happy to share, with kids, grown ups and old fogeys. I fit at least ONE of those, I think, ..