I have just finished rolling some 375 RUM's for initial load development using Redding dies, but I do not have a lee factory crimper yet so I had to use the crimp in the seater die. Although I set the die so I can feel the brass get "crimped" at the top of the stroke, it really does not look at all like it is crimped. How do you folks do it?

When I load my 7mm Rem mag I use the Lee crimp die. The 7mm bullets I load do not have cannelures, but with the Lee crimper I can see marking on the brass(I do not crimp till the bullet is dented). I have been accustomed to watching the Lee crimper do its thing when a round is in it, and I cannot see it with the Redding die. Maybe I am just being picky...

Forgot to mention that my seating depth with the Northfork 250's is nowhere near the cuts in the bullet shank, so no cannelure or groove to crimp in.

I do it all at the same time...use a very light crimp so as not to buckle the case as you probably do not use a file trim die and the variation in length of your cases turned in a rotary trimmer will make your crimping uneven from case to case...

But with the RUM, try this, take about .004 off of the resizer button as that will give your neck a strong puchase of the bullet, then use a bulk powder that fill to half way up the neck and you won't need a crimp.....

That sounds like a dandy idea. I have to shoot what I have already over the chrono to see if I have crazy variations, and also the thought of the bullets getting seated further while in the mag when the rifle is fired is something to take into consideration.

That .004 off of the expander won't give me too tight of a fit, will it? When I seated the bullets, they went in with a fair amount of resistance, did not go in like the fit was too loose... I only ask because I do not know what a tight fitting bullet feels like in the press compared to normal neck tension.

To test bullet seating resistance, take the expander button off, resize one case, and try to seat a bullet in it that way. Now you can get the feel of it.

Well, after shooting my rifle today, I found out my rifle has a real tight throat. My reloads are very difficult to close the bolt on. You could see the marks on the necks of the brass. I did not shoot those that were exceptionally hard to close, I do like my facial features if you get my drift...

I at least got a couple to chamber without too much effort. I did not mike my necks after loading, nor did I chamber any rounds to make sure after rolling em at the house. My fault all the way around. Since this rifle was a prototype, I figure Remington did not use the same reamer as what was used for the standard production rifles. Guess I should solve that issue before I go any further with turning down the sizer button on my die.

Just a thought, I always seat the bullet in one station and then crimp in the next to avoid moving the shoulder back at all. I do this with either a roll crimp for cannelured bullets or a tapered crimp for smooth bullets. I also use this for both cast and jacketed bullets.

I scounge dies at gunshows and garage sales to get my extra crimping dies. Yep, I am a cheap old bast....