Do I need to crimp my 45/70 loads?

[5Shot]

Running high pressure loads in a Ruger #1 (I hate Autocorrect!) with H335. Do I need to crimp these for good ignition or is neck tension enough?

[seaboltm]

Depends. In a single shot I would say no. In a lever action repeater, I would say yes. I think you mean Ruger #1? In that case, no crimp needed.

[petroid]

I agree. Anything with a magazine should be crimped to prevent bullet setback from recoil. Single shot not required.

[5Shot]

I think you mean Ruger #1? In that case, no crimp needed.

Dang Droid always changes Ruger to River with Autocorrect and I missed it...

Thanks for the replies.

[bbqncigars]

You might check with Hodgdon on that. Or a good loading manual (Lyman, etc) will tell you if a heavy crimp is needed for the powder. I'd look in my various manuals, but I'm on the road right now. The loading data on Hodgdon's site only lists copper condom slugs. :evil:

[FLHTC]

A Lee Factory crimp die would be good for jacketed or cast, if you find you do need to crimp. I never liked roll crimps since it works the case mouth unnecessarily but the FCD snugs the bullet just right in my opinion.

[John Boy]

In a single shot rifle, the only crimp that is needed is to remove the expansion bell on the case after the bullet has been seated. Magazine fed rounds = full crimp

[montana_charlie]

A crimp (or lack of one) can establish burn characteristics of smokeless powder.
For a starting point, check the manual on your selected powder.

CM

[seaboltm]

In a single shot rifle, the only crimp that is needed is to remove the expansion bell on the case after the bullet has been seated. Magazine fed rounds = full crimp

The reasons to crimp that I can think of:
1. tube magazine
2. remove the expansion bell on the case
3. powder choice requires a heavy crimp for better ignition (H110)
4. the powder load is heavily compressed by the bullet therefore crimp in order to keep the bullet from being pushed out by the powder
5. heavy recoil that cause projectile movement, especially in revolvers with heavy bullets moving fast (300gr 44 mag and larger)
6. semi-auto pistols that would tend to push the bullet farther into the case when feeding into the barrel.

Those are really the only reasons I can think of

[Toymaker]

For my 45-70 black powder loads I size, trim and chamfer new cases, trim to a consistent length which may be longer that what is stated in the reloading manuals, fire-form the cases and never size them. When shot they're de-primed and dumped in a bottle with soapy water. I rotary tumble them with stainless steel media when I get home, dry and store until the next reloading session.
Cases for smokeless loads are treated the same way except I full-length size them and check the length before reloading. Generally they need to be trimmed a tad after 4 or 5 uses. Usually its just evening up the case mouth. Nothing is crimped and everything gets annealed after 5 uses. There aren't any shoots in December so that month is reserved for the case work.
All cases are Starline and I haven't had any cracks, separations or other issues. Primer pockets and flash holes are in good shape too. I shoot 11 competitions a year plus practice and I really have no idea how many times they've been reloaded - I quit counting after 5 years.