Question on crimping

[DrMike]

It will be necessary to avoid attempting to impose a roll crimp when using a bullet without a cannelure. In effect, you are distorting the neck by attempting to crimp. There is sufficient neck tension to hold the bullet in all save a few exceptional calibres. Try seating a few bullets w/o attempting to crimp. It should fix the problem.

 

[BK]

It will be necessary to avoid attempting to impose a roll crimp when using a bullet without a cannelure. In effect, you are distorting the neck by attempting to crimp. There is sufficient neck tension to hold the bullet in all save a few exceptional calibres. Try seating a few bullets w/o attempting to crimp. It should fix the problem.

Thanks, Doc. That's what I was trying to say, but you did it much better.

 

[FOTIS]

1 step for seating and crimping. Iwasn't crimping these until I noticed that some of the bullets were loose.and then when I tried to adjust, I got nowhere. other than some funky lookin cartridges. :shock:

Ok if you must crimp do this.

Put an empty case in the shell holder and raise the ram (lower the handle/raise ram). Screw in the die until it will not go in any more. At that point you reached the start of the crimping effect of the die on the case. Raise handle/lower ram, screw in die 1/2 to one full turn and lock it. At this point you are crimping correct. ( You're going to play with this to get the seating right). Another thing that most of us do not factor in is that different amounts of crimp raise and or lower pressures.... hence velocity etc......so consistency can play a huge role in accuracy! This is why I avoid it unless absolutely needed. By the way on a ruger #1 I crimped just a little bit but only on my 458 win and 458 Lott. The only reason is that I had to expand the mouths to seat the bullet (without crushing the cases), so I closed the mouths....again just a bit. That is it!
With a 7mm rem mag no crimp whatsoever is necessary especially in a single shot since the recoil will not effect your next round, since there is no magazine with rounds in it.

 

[Ol` Joe]

Try sizeing with the expander removed and see if a bullet is still loose.

Measure the expander ball, it could be the wrong one for your die.

Is the seating die screwed all the way in the press and possibley crimping as you seat? Try screwing it in just until it hits a case in the shellholder with the ram raised then backed out a turn to stop it from crimping. If you crimp too much or apply crimp while the bullet is still seating it will bulge the case neck behind the crimp loosening the brasses grip on the bullet.

 

[1Shot]

I have found this through much trial about the Lee Factory Crimp Die. I do a lot of shooting of the old WWI & WWII era rifles. Most have long throats and you can't seat a bullet out close to the lands and get them to work through the magazine. By seating them normal and using the Lee Factory Crimp Die. I can get the same great accuracy as I would by seating the bullet close to the lands. I get much better accuracy with a crimped bullet than one without the crimp in these rifles. I guess this is the result of what Lee says about the retard or holding the bullet for that nano second so the pressure builds up before the bullet moves so you get a better burn. All I know it works in these old long throat rifles.