to crimp or not to crimp

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15 years 11 months ago #2723 by haskell
to crimp or not to crimp was created by haskell
i have a supply of sierra bullets without a grove to crimp with. can you crimp them anyway, and will it hurt performance? i was always told you HAD to crimp for semi autos. any help or ideas would be great. thanks ahead of time, you have a truly great site here.
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15 years 11 months ago #2724 by DMCI*
Replied by DMCI* on topic Re:to crimp or not to crimp
Sierra makes match bullets and long range or accurate hunting bullets.

Match bullets are not crimped. Reason is crimps are not generally consistent. Match shooters (Well, I do.) value consistency above all else. Consistency of bullet release on firing is very important.

If you need to increase bullet retention strength, you can fiddle around with the concept of tapered crimp by slightly increasing depth of seating die. (not the seating depth, but the seating die itself.

Hunters generally have a large target and for humane reasons don't generally take game over three hundred yards, except in the case of a few cloven dudes that sit out there or varmints.

That is why sierra target and hunting bullets have no crimping groves.

For tubular magazines, like on saddle guns, crimping is very important. You will note that bullets intended for them like .30 cal 150 or 180 RN bullets generally have crimp groves for this reason.
The following user(s) said Thank You: jtallen83
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15 years 11 months ago #2725 by Latitude 64
Replied by Latitude 64 on topic Re:to crimp or not to crimp
I would definitely not try to crimp the bullets with no crimp grove. I use a slight taper crimp even if the bullets I am shooting have a crimp grove. I shoot mostly non-cannalure bullets but since I buy a fair amount of mil-spec bullets from Widener
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15 years 11 months ago #2726 by a Guest
Replied by a Guest on topic Re:to crimp or not to crimp
Boys I'll go ahead and make some mad with this but I've been loading for 45yrs and this discusion never goes away and I don't understand why it don't go away. If you ain't got a machine gun or a saddle rifle you ain't got any business crimping rifle rounds. Most dies don't have the right crimp design for a machine gun. That leaves us with the 30-30, 444, 45-70s and those old saddle type rounds for crimping. 002 to 003 grip is all that needed on the case with std rounds. Now if you may have some issues with some powders not burning as well in cold weather but you swith neck bushings for more grip and go to a hotter primer. Stick powder lites up easier than the ball powders so thats a hint for cold weather. Crimping does not aid in accuracy and generaly hurts it. It was needed on the older cowboy ammo. There were a bonch of test that were run by the Herters brothers in the 50s and 60s and in their book which I'm sure that would be impossible to find these days they had some rounds with a double sholder on them. They looked like some of the old space rockets. But to the point I never found anything in that book that hasen't been able to be applied today. They had their act together back then and there is nothing new in case or bullet design that will apply today. I remember one of the reloading statements was crimp as light as you can get by with. Old Jaques Herters had something to do with the German caseless ammo development in WW2. He stated in the book that it might come but will go back then. Look at the HK G11 for example, the best caseless rifle so far but being caseless it over heated badly. Rifles like our black guns use the case to extract heat so this aint changed none. The HK needed a cooling system on it. Crimping used where needed is fine but the other areas that it is being used is very hard on the brass. I load the brass untill the primer pocket finially will not hold a primer or a neck split or the case gets lost in the grass. I set brass up as a group and I may get a 100 loads off of if, and they will shoot as a matched group untill they are scraped. I wouldn't get by with that crimping the cases. Do whats best for your style of shooting. MSH
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15 years 11 months ago #2727 by Hank in Arkansas
Replied by Hank in Arkansas on topic Re:to crimp or not to crimp
I certainly won't dispute anything that others have posted on this thread, as these observations come from a lifetime of handloading and are correct. However, here's my 2-cents worth. Handloaders must insure that bullets are not dislodged during the shooting process. The feed cycle can shove them deeper into the case (not good), or the recoil impulse can cause them to migrate out of the case (also not good). The objective is to keep the bullet right where it was seated during the handloading process. The military has settled on crimping, as have the factories in most applications. Military ammo often even applies lacquer, both for waterproofing and "gluing in place". But none of that is necessary IF the correct neck tension is present. Here's what I'd advise a beginning handloader: if you seat a bullet, and can push that bullet deeper into the case with hand pressure, by pushing the bullet against your loading bench, then neck tension is NOT great enough to be safe in a semi-auto rifle or pistol. Also, I agree that taper crimping is a good idea, but if a novice overdoes it, taper crimping can actually lessen neck tension by bulging the neck wall away from the bullet. The Lee Factory Crimp die overcomes this problem IF you decide to crimp. Again, proper neck tension should suffice, but the bullets must be "locked" into place for semi- and full-auto guns. If that means crimping, so be it.

One more observation. Neck annealing can make case necks very very soft, so much so that neck tension is very dubious. I'd recheck neck tension with each new batch of cases, particularly if they are of the foreign military surplus variety. No telling how much or how little they annealed the brass, thus effecting neck tension. I use lots of mil surplus brass, but I always check out my first reloads to make sure that neck tension is correct.

I've used the Lee Factory Crimp die on lots of uncannelured bullets with good success, but I'm NOT a match shooter. I would agree that this step is not best for ultimate accuracy, but is best for safety. (My humble opinion.)
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15 years 11 months ago #2728 by BUILDING MY SASS
Replied by BUILDING MY SASS on topic Re:to crimp or not to crimp
MSH, not to pee in your pound...LOL but why do most manuals suggest doing it, especially for the semi-auto..?
Now as I have been told, SA yes Bolt no, or if you are building match ammo...as you said.
I will have to pull apart a few shells to see if my Hornady's are crimped.
BMS
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15 years 11 months ago #2729 by a Guest
Replied by a Guest on topic Re:to crimp or not to crimp
Its the same reason 60% of the cost of your A10 is pissed away on lawyer fees, to cover their rears. They also say in the reading material its for referance only and other warnings inderictly state we reloaders are stupid. It does not bother me I've listen to this for a long time. I have the winnings sitting all over the shop and not one of those trophy's had a crimped bullet, so my come back to all is how many of you did see in the past at the big matches. Do you have 2 world championships in international competition. Tubb has 11 nationals but no world cups so thats where I'm coming from on that issue. This discusion will never go away but my point is if you crimp you will crimp your groups and thats just the way it is. I wonder why the AMU don't crimp their match ammo. Wonder why the Marine rifle team don't crimp their ammo. This is one of the reasons I don't like to talk reloading and keep lots of this stuff to myself your just as safe to go fart in church if you know what I mean. My Loading data book that I leave to my boys will be some best kelp info around.MSH
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15 years 11 months ago #2730 by BUILDING MY SASS
Replied by BUILDING MY SASS on topic Re:to crimp or not to crimp
MHS,,,,LOL, hey I didn't mean to grab the bull so to speak, just asking a follow up question....that is how we learn...right...and I use a Lee Crimp Die..
You have done well in the shooting world, I respect your opinion....That is also how we learn from our elders...and the experience of men like you...

That book you are talking about, maybe my Grandson might get to read it someday...LOL
BMS
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15 years 11 months ago #2731 by a Guest
Replied by a Guest on topic Re:to crimp or not to crimp
Well don't mean to come on hard about this and aint mad in any way but remember lawyer fees and that 60 plus %. That aint no bull. They work this indursty like flys on a cow flap because its easy and courts have played into it and thats why I said to go back to the older books like Herters and PO Ackly to get the real skinny. Like I said this aint going away and with the younger group that is starting to reload that thinks whats in print is always the truth. There are disclamers in every loading manual for the info that they produce. Lawyer induced. In my book if you aint willing to stand by what you print you need to go to Washington and work with those SFBs. I have a problem with the approch that is taken by companys legal depts dancing around issues. I deal with these issues with students often. So understood but look back 40 to 60 years for the best info on loading and I think you will see what I mean and apply it to modern times. This is a better way of making the point. Read PO Ackleys book and try to find the Herters manual.MSH
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15 years 11 months ago #2732 by a Guest
Replied by a Guest on topic Re:to crimp or not to crimp
I forgot to also say that I also blend some powders for some match cals to get better preformance. Dad taught me a few things on that. I don't advise that to fokes but every now and then I'll see an artical on that pratice and the old farts that are doing this are of another time. As a matter of fact I ask one of those buzzards the other day what T-Rex looked like and got a ^%$^&&*(^%$#$(&%^# answer back.MSH
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