I am trying to load 235 gr. Speer bullets for my .375. They do not have a cannelure. I can wiggle some of them and have to use a crimping die to secure them to my satisfactions. I am not haveing any problems with bullets that have a cannelure.
Do i need to play with my seating depth to get a better role crimp?

for ~75 bucks corbin has a cannelure tool .. don't bother with anything else

find where the bullet is .375.. mark the top and bottom .. you can taper crimp anywhere within the marks

If you can wiggle or turn the bullet in the case neck there is something amiss in your loading procedure. "Crimp" is not meant to be used as a "band-aid" for poor neck tension. The interior neck expander ball should idealy be sizing the interior of the case neck about 0.002 to 0.0025 smaller than the diameter of the bullet you want to use. Trying to force a "roll" crimp onto a bullet without a cannelure will either damage the smooth sided bullet or buckel the case at the neck-shoulder junction (or both). At the very least it will cause a lessening of the tension between the case neck and the bullet and that can have a (sometimes significant) negative affect on velocity/accuracy.

quote:

Originally posted by R D McMillan:
If you can wiggle or turn the bullet in the case neck there is something amiss in your loading procedure. "Crimp" is not meant to be used as a "band-aid" for poor neck tension. The interior neck expander ball should idealy be sizing the interior of the case neck about 0.002 to 0.0025 smaller than the diameter of the bullet you want to use. Trying to force a "roll" crimp onto a bullet without a cannelure will either damage the smooth sided bullet or buckel the case at the neck-shoulder junction (or both). At the very least it will cause a lessening of the tension between the case neck and the bullet and that can have a (sometimes significant) negative affect on velocity/accuracy.

Search for "Neck tension" and you will find out quite a bit about this. If you have a micrometer, take out the expander ball of your sizing die and measure it. For a 375 it should measure about .373-.374. If it is big (and I suspect it is) you can gently chuck the stem in a drill press and polish it down until you get the desired tension on your bullets. It has probably been large all along but the crimping was hiding it.

Crimping in bullets is generally a poor idea, unless you're not too particular about where they go once they exit the muzzle. After all, how many benchrest shooters do you think crimp their ammunition?

As has been pointed out, your cases are not providing sufficient neck tension, probably due to an oversized expander nipple. Solve that problem, then back your seating die off of the shellholder sufficiently to negate the crimper built into it.

I checked the expander with a micrometer, it measures .373". I reset the die per the instructions and ran one through it. I could put the bullet in by hand. I added another 1/2 turn per the instuctions and it fixed the problem. I reloaded the 14 bullets i had left and there was know problem with any of them.

quote:

Originally posted by Thunder Head:
I checked the expander with a micrometer, it measures .373". I reset the die per the instructions and ran one through it. I could put the bullet in by hand. I added another 1/2 turn per the instuctions and it fixed the problem. I reloaded the 14 bullets i had left and there was know problem with any of them.

Sounds like you are using a Lee Collet die? Otherwise, turning a conventional sizing die down a bit would make no difference.

The Lee Collet die is a great invention and I have several and use them almost exclusively for certain calibers. However, they are famous for having expander diameters which don't allow enough neck tension. Chucking the expander into a drill press and taking about .002" off of it will help your neck tension. Another trick is to rotate your case about 1/8 turn as you withdraw it part way from the sizer, then reinsert it to allow the sizing petals to hit approximately the "tops" of the small gaps between petals on the first sizing. This not only makes the neck a little tighter, it also ensures that it is rounder.

Thunderhead: While I don't shoot the 235's in my 375 H&H, I do crimp all the other bullets. Why? I don't want them moving in the magazine under recoil. If you happen to be in a situation, where you need a follow up shot on a particular critter, you want your ammo to feed easily and without hesitaton.

The 375, is accurate enough with just about any load, to shoot whatever you want at any reasonable range.

Jerry