Title pretty much says it all. I have done a little experimenting with this but not really enough to come to a conclusion. I've recently been working more with black rifles and crimping all ammo for those just because I feel like they need it. For my bolt rifles it seems the crimp either doesn't effect accuracy or maybe results in a slight improvement. I use the Lee Factory Crimp dies. What do you guys think?

It depends on several things:

I crimp magazind loaded cartridges for the Win. and Marlin lever guns as they are bullet to primer and tend to set bullets back

I crimp .375 H&H and Ruger and up in bolt guns as recoil sets bullets back with pounding on the front of the magazine under certain circumstances, so its a proper thing to do...

I don't crimp calibers such as the .338 and below as they don't set bullets back in my reloaded ammo, but I do take other cautions such as using a powder that mostly fills the case and I may turn off a thousands or two off the die expander ball to give it a tighter fit on some recoiling rifles. I never crimp on rounds like the 06 and 270 or below and of course not on .222, 243, or 257 for instance..

I crimp all double rifle loads..

I crimp all pistol rounds.

As you can see, some you duz and some ya don't!!What you do is use plain old common since.

I don't crimp any rifle ammo under 375.

I crimp everything I reload.

I crimp every thing I reload, too.

My thought is if the ammo makers do it there may be a good reason.

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I crimp everything I reload

Just curious as to why?

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Originally posted by ramrod340:

quote:

I crimp everything I reload

Just curious as to why?

It's a 3-second operation that (to me) makes my ammo more consistent. And i like the fact it removes the "shoulder' from a fresh-trimmed piece of brass, even after chamfering. If I'm going to go through all the minutae to reload, I might as well make ammo as good as can be. Seems to work.

So you only use bullets with a cannelure?

Does personal choice account for anything????

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Originally posted by ramrod340:
So you only use bullets with a cannelure?

Yes. But you don't need a cannelure to use a crimp.

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Yes. But you don't need a cannelure to use a crimp.

Knew that was an option just never tried it. If you feel it gives you better ammo then I would stick with it.

I've gotten lazy in my old age. I trim a touch short and let the brass grow. I usually lose it before I need to trim again. Various necks would suck at crimping. For years I took every step possible to get the best I could. But for some reason didn't crimp smaller rifles. Now days I could care less if it groups .75 or .8". I found as the number of rifles I reloaded for went up the time I spent on each went down.

A reloader should put as much effort into his craft as he needs to build ammo he has total faith in.

"Makes ammunition more consistent", eh? Check to see how many benchrest shooters crimp their ammunition.

Crimping is rarely indicated and should be avoided except with certain rounds and guns.

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Originally posted by Stonecreek:
"Makes ammunition more consistent", eh? Check to see how many benchrest shooters crimp their ammunition.

Crimping is rarely indicated and should be avoided except with certain rounds and guns.

If you can't understand that this is all voodoo there is little use in explaining.

Don't misunderstand, I';m an average shot at best, and my net benefit from reloading is zero, probably less than zero. I do it because it's something to do that has to do with guns. And I couldn't care less what benchrest shooters do. Like most other things in life, I tend to do what pleases me, not what pleases others.

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A reloader should put as much effort into his craft as he needs to build ammo he has total faith in

Exactly.

Case length is not as critical using a collet type crimp die like the Lee. All interesting replies, thanks.

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Originally posted by BaxterB:

quote:

A reloader should put as much effort into his craft as he needs to build ammo he has total faith in

Exactly.

Me too. The only thing I crimp are cast bullets. Otherwise it isnt even an afterthought. But it is purposeful for some weapons. For instance I used to crimp 35 Remington rounds for a tube fed Magazine.

I have no comment on whether to crimp or not.
I don't unless it's necessary.
That said, I know why the factories crimp, and it's all due to SD, they use whatever powder they can get CHEAP and blend it to give the desired ballistics/velocity. How they get uniform ammo with the often 60% fill ratio they use, is by crimping to boost start pressure, this in turn raises peak pressure and normally gives very good Standard Deviations.
This is why factory ammo performs in many different gun chambers, all of which may vary tremendously.

Cheers.

quote:

Originally posted by Stonecreek:
"Makes ammunition more consistent", eh? Check to see how many benchrest shooters crimp their ammunition.

Crimping is rarely indicated and should be avoided except with certain rounds and guns.

I would think that benchrest shooters take numerous other steps to ensure uniformity and consistency. Those steps would render the crimp step unnecessary. With the Lee factory crimp die it's a quick and simple step that may help offset some inconsistencies the non-benchrest type reloader may be working with. I have been using Lee factory crimp dies for some of my reloads for nearly 20 years. I don't have the definitive data to substantiate it, but my best loads for each rifle tend to have a light crimp.

It goes back to what the other poster said about doing whatever it takes to give you faith in your reloads.

I crimp our 375 Weatherby, 416 Rem and 500 Jeffery. In particular the 500 Jeffery will set bullets back that are in the magazine. For our 270s I don't.

I've found crimping, cleaning primer pockets, and tumbling brass are a waste of time for hunting ammo.

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Originally posted by JGRaider:
I've found crimping, cleaning primer pockets, and tumbling brass are a waste of time for hunting ammo.

For the average hunter, we could probably add reloading to that list as well, when it comes down to it. Factory ammo is damn good these days.

No, I don't crimp centerfire rifle ammo up through the 338 diameter. Yes, in the bigger stuff which will be used at much shorter range and only then with a bullet designed to receive the neck-crimped brass...which has to go somewhere!

There's no need for it in a bolt rifle and there's no way crimping "makes up for other reloading deficiencies". Crimping, with most bullets, is a sure-fire way to make ammo that no longer fits the chamber and or actually reduces the neck tension making the bullets way more loose in the neck than before crimping was attempted.

You'll not find bolt-gun shooters who crimp and demand top accuracy. Maybe good enough is good enough for some.

Maybe with the above "trick tool" you can make ammo that will still chamber and have sufficient neck grip but it's an unneeded step at best.

That's just my 2 cents so I hope no one gets offended just because they're doing something wrong!!

There, I feel better now.

Zeke

Just being the average hunter/shooter/ reloader and avid reader of most manuals I crimp almost all my ammo. Consistently I see questions on neck tension , most of the time with inconsistent neck tension.

The only ones I don't crimp are reloaded using the LeeLoader. It gives plenty of tension. The kinetic bullet puller I use when I make a mistake provides the evidence of that.

However, when using the collet neck sizing dies it is impossible for me to be perfectly consistent case to case. I accept this and seat the bullet anyway ,then crimp it in place with Factory Crimp Die. Easy. From 50yds to 250yds my ammo shoots very well off a solid rest.The ammo is carefully put together thru ALL steps except tumbling. I polish with steel wool.

I load for my brother`s 243Win using the method above and my rifles also. At over 200yds in an open field he had a bang flop on a nice WV doe with the Hornady 100gr BTSP over 34.2gr of IMR4064 and WLRM primer. He said, "Don't ever change that load !" My shot this year was an open field shot at 150yds or a bit more with the 30-06/Hornady 150 SP/over 47gr of IMR 4895, off tall adjustable Primos sticks. Yep bang/flop. The method just plain works for the average guy.

Target shooters have other issues to worry about and 250yds and under on a moving target off sticks is not a concern. They deal with earth spin,humidity,wind, bullet yaw,elevation, and the like and much farther targets.

I for one have seen no adverse effect on carefully assembled ammo that has been crimped at the ranges of 50yds - 250yds and for hunting purposes.That includes the non cannelured bullets also.

quote:

Originally posted by ZekeShikar:
No, I don't crimp centerfire rifle ammo up through the 338 diameter. Yes, in the bigger stuff which will be used at much shorter range and only then with a bullet designed to receive the neck-crimped brass...which has to go somewhere!

There's no need for it in a bolt rifle and there's no way crimping "makes up for other reloading deficiencies". Crimping, with most bullets, is a sure-fire way to make ammo that no longer fits the chamber and or actually reduces the neck tension making the bullets way more loose in the neck than before crimping was attempted.

You'll not find bolt-gun shooters who crimp and demand top accuracy. Maybe good enough is good enough for some.

Maybe with the above "trick tool" you can make ammo that will still chamber and have sufficient neck grip but it's an unneeded step at best.

That's just my 2 cents so I hope no one gets offended just because they're doing something wrong!!

There, I feel better now.

Zeke

No offense taken at all Zeke. My experience is anecdotal at best and always will be. I have certainly never had any issues with it and as I mentioned earlier, it seems my best loads (hunting rifles) almost always have a light crimp. The factories are doing it and Lee has better than anecdotal data, so I would assume there can be some value to it.

I only (taper) crimp pistol and revolver loads (for the latter and contrary to roll crimping, case length is not critical for a taper crimp). None of my rifle loads gets crimped, up to 9,3's.

As usual with any gun subject if you have two experts evaluating you will get three opinnions!!

That said, why does it have to be yes or no, black or white?? that ridiculas, crimping must be used sometimes but not all the time..

I wouldn't dare use a double rifle without a crimp or a big bore bolt action of 40 caliber or a big bore lever action with all that recoil working on a 7 rounds end to end in a tube magazine..I crimp big bore DG rounds and those that don't are begging for trouble.

By the same token crimping a caliber short of a 375 is probably a waste of time, but that's your choice..I never crimp a 338 Win or lesser recoiling round in bolt actions or any Savage 99...

Ive run a lot of tests over the years and accuracy wise can't be determined by all the shooting in the world was my results, so if the bullet will hold, I don't crimp, but one consideration to keep in mind is a crimp is very hard on brass and split necks come early.

I reload only few calibers. Crimp everything:

8x57JS + Norma Oryx - Lee Factory Crimp
.375 H&H - Lee Factory Crimp
.460 Rowland - RCBS Taper Crimp
.500 S&W - Redding Profile Crimp Die

All crimping is the separate step after seating.
I crimp to cannelure only for .500 S&W.

Jiri

I crimp all my ammo (except my 300 WBY) with the Lee die whether the bullet has a cannelure or not. On my 8x57 it makes a big difference on my accuracy.

I spent quite a few years (and a whole lot of energy and cash) benchrest shooting. Nobody that I know of in that game crimps. Of course we are a very careful (anal) bunch that would do anything possible to produce better groups.

The only rifle hunting ammunition that I crimp is in cartridges of .375 H&H or larger with the exception of the 22 Hornet. The Hornet has such a thin case that crimping helps provide enough resistance to allow the powder to burn more consistently.

If you think it helps anything then have fun and crimp your cartridges. My chronographs have not shown it to be of any benefit for me but to each their own.

I don't actually crimp my 6.5 Creedmoor, but I do just lightly roll the case mouth in a small amount. Just can't stand to have a lip at the bullet/case junction.
I like lots of neck tension and a good crimp. But then any of my ammo may Need to be water/submersible proof. I definitely crimp my 375 Whelan AI, 9.3, and anything larger.
Any bullet that can be pulled from a case with my fingers is incomplete ammo. 1-3 thousands neck tension may be super accurate in some rifles. But that accuracy potential is useless if the bullet is almost falling out of the case or a compressed load pushes the bullet out far enough that a round cant be chambered.
Consistent annealing really does help if someone doesn't want to crimp. With the Anneal Rite machine good consistent annealing is easy.

I only crimp big kickers.

I only crimp my strait walled .400 to .500.

Thanks for all the replies, some interesting ideas. I didn't crimp any rifle cartridges for the first 40 years or so that I've handloaded but I am crimping some now. Just another one of those variables that makes our sport interesting.

Cold Trigger Finger if you can pull a bullet with your fingers, crimping is not the solution, I would in such a case (and I have) chucked he expander ball stem in a drill press and turned a thousands or two, and even three in some off the ball with a file and polish with some emery paper, or you can do the same in a lathe..That will give you a snug or tight neck, your choice..Sometimes I do this on double rifle or big bore bolt action rifle dies, then use a powder that fills the case, and then with a tight neck and a full case I don't really need a crimp, but I will add a light crimp just to be safe..It works real well.

IMO a crimp is something you use only if and when its needed otherwise your over working your brass to some extent. I try not to use one.

I shoot F-Class Open at mid and long range (300-1000 yards), with a some amount of competitive success. At the top, the keys to winning are a great rifle with great ammo and reading conditions. A single point or X can often times win a tournament.

Reloading wise, NO stone goes unturned. It's crazy, really. What I can tell you is that NOBODY crimps. If it helped people would do it; anything for an edge. Lots of people have tried, and it does not help.

Crimping serves one purpose: to keep bullets from moving from their original seating depth, it does not aid in accuracy. Crimping is called for when optimizing function over accuracy; when severe recoil or rough handling are a concern.

I crimp my pistol loads, my .45-70 (which is a giant pistol case, IMO). All my hunting rifles get standard neck tension and my target rifles get very closely controlled, minimal neck tension. I would also crimp if I were loading a big boomer for dangerous game at close range.

-nosualc

I crimp all of my .416 Rem Mag ammo because it's the smart thing to do. I do not crimp my go-to .35 Whelen loads because it hasn't improved accuracy, nor is it necessary to keep bullets from jumping, or getting pushed back into the case.

That said, some of my .35 Whelen loads have showed increases in accuracy with a light crimp. However, none of these loads shot better than my current hunting set-up, so they never made it off the test-floor.

Regardless of caliber, if the bullet has a cannelure, I will try crimping at some point either for the hell of it, or if I believe it might help reliability of a hunting round.

Many love to preach that each rifle is an exception unto itself, so why casually dismiss a variable as useless until you've actually tried it?

Finally, I don't benchrest shoot so don't know; but do any benchrest competitors use factory ammo? I assume ammo like Federal Gold Medal is crimped?

I crimp in my two progressive presses for our .223 AR ammo at station #5 because it is a free operation

I generally do not, but I've seen loosely seated bullets jam in the throat and stick when the unfired round is ejected at the end of the day.
This is a little worrisome, to me.

Tom,
That is something that pops its ugly head up form time to time and has to do with your dies as a rule..pull the threaded stem out with the expander ball on it and turn 100 to 300 thousands off the ball..that will tighten up those bullets in the case and you will no longer need to crimp..

Also seating bullets too long causes them to wedge in the rifles throat, seat them off the lands..

quote:

Originally posted by Atkinson:
Tom,
That is something that pops its ugly head up form time to time and has to do with your dies as a rule..pull the threaded stem out with the expander ball on it and turn 100 to 300 thousands off the ball..that will tighten up those bullets in the case and you will no longer need to crimp..

Also seating bullets too long causes them to wedge in the rifles throat, seat them off the lands..

100 to 300 thousands ?

Ray.....rethink that a spell