45-70 crimp question

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I crimp everything,to one degree or another.
for single shots,just a little 'squeeze' to iron out the flare and a tad more for ...well,just because I think I should.
 
I do, simply because I seem to get a better burn of the powder with a good crimp. I also shoot my .45-70's in both a single shot and lever action rifle, so the crimp is required in my case.

Hope this helps.

Fred
 
glockky,

I have shot only 7 rounds out of my 1st 45-70 rifle, it's a H&R 1871 Buffalo Classic. The first 15 rounds that I loaded were crimped into the crimping groove on the Lee 405 gr FPFB cast bullet. The reason I crimped was because the BP loading of 65grs (volume and weighed) FFG was very compressed.

I resized those fired cases only enough to hold the bullet tightly and was able to get 70gr FFG which is even more compressed and I did not crimp, but used a black marker to mark a reference at the case mouth bullet junction, that way I can tell if the bullets walk.

As R'fred mentions if you are shooting a smokless load which is low volume (except for powders like TrailBoss) for the 45-70 you will probably want to crimp to make sure the pressure does not start the bullet down the bore prematurley.

Another way to make sure the burn is complete is to find a bullet that will chamber close to (jacketed) or on the (cast) lands.

Any other smokless powder rifle loads that I shoot in bolt actions-single shot are not crimped but my 1 lever gun is.

By the way 7 shots of 45-70 405gr 65grs BP is a pretty good thumper, it was able to transfer the H&R BC's case coloring from the butt plate through my shirt and onto my shoulder.:D
 
Heck no. That 45-70 brass is expensive. If you "have to" in a single, you're pretty much doing it wrong.

Wait a minute.. whatever RC says.
 
The answers I am getting kind of confirm what I was thinking. I dont think I need a crimp but didnt know if would affect powder burn by not crimping. I use IMR 4198 if that helps
 
I fire mine in the same Sharps so I never resize or crimp. I am still shooting some made in the 1880s but have decided to put the empties back in the original boxes and leave those alone.
 
Just for longer case life, I would not crimp for a single-shot.
Unless I was using massive charges of slow powder where a crimp might promote a better start burn.

But IMR-4198 will not be a massive charge, and it isn't slow burning and is easy to light.

rc
 
I'd like to not crimp for the trapdoor, but here's a problem I've had. I bell the mouth out to accept large cast bullets, and prevent any distortion of the round. I believe this is even more critical with soft lead PPB's. Now that works great, but you're left with a belled mouth that tends to snag and sometimes gives resistance when loading. And there's also the issue of exposure to elements for a load being worked up for hunting. You can't have a water-collecting space between the case and bullet.

So how do you set a die to eliminate the bell after seating but not give you a hard crimp? Some kind of second full resizing with the decapper pin removed? Or a Lyman taper crimp die?
 
After seating the bullet to the depth you want back the bullet seater stem all the way out so it doesn't push the bullet down any farther, screw the seater die body in in small steps untill it irons out the flare and call it quits. I don't screw the die in until the press cams over and roll crimps, I set mine as stated above. Another choice is using a Lyman M die it doesn't bell but rather sizes in two steps to enlarge the case mouth, then go to your regular seater crimper and set it as above. It kind of taper crimps when set like described.

Heck I guess you could use a taper crimp die if you can find one the correct diameter.
 
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for a single shot, I would crimp, but not for anything else other than to make sure the fire is going before the bullet starts down the bore.. and I wouldn't whammy them like a .454 wheelgun, just enough to say "it's crimped"
 
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By the way 7 shots of 45-70 405gr 65grs BP is a pretty good thumper, it was able to transfer the H&R BC's case coloring from the butt plate through my shirt and onto my shoulder.:D

I had a Ruger #1 that at one point, got loaded to the point they were knocking on the door of the .458 Win.
50 gr. of VV N135 under a 405 flat point.
After three rounds, your self-preservation instinct kicks in, and you put it back in the case and shot something else..

Now I've got a .444 Marlin... :banghead:
 
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Some kind of second full resizing with the decapper pin removed?
NOoooo!
That will resize the bullet undersized when the brass goes in the sizing die and comes out under size again like it was before you belled it!!

Just adjust the seating die as dagger dog said above.

But, all your brass has to be trimmed to the same length for that to work real well too.

rc
 
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