Disclaimer: I'm new to reloading


So I've loaded and fired about 50 rounds without issue. I've been trying out different powders/bullets/etc. using the OCW method and haven't had a problem yet until today. I'll try to provide as much information as I can here.

I reloaded 18 rounds to try out some IMR4350 and the bolt won't close in my rifle. I'm reloading once fired factory Remington ammo.

-Cases are 2.484" in length.
-OAL from O-give to head is 3.843" which is 0.025" off the lands and has been used without issue for the previous 40 or so rounds I've fired that are the same bullet.

-After resizing they're .440" right at the shoulder. (SAAMI spec .441")

When I test the (empty) case here they go into the chamber fine. I believe I've found the problem in that after it is reloaded this same measurement is now .445". With this measurement the bolt will close but is more difficult. Taking the same measurement after I've chambered the round the same measurement is now .443" and it is slightly easier to close the bolt but still more difficult then the empty case.

It seems while seating the bullet it's swelled the case at the shoulder. Why is this happening?

My reloading equipment is all new RCBS. I'm using a single stage press.

The rifle is a remington model 700 long range.

The loads are not compressed.

Well after messing around all morning with this and not figuring it out, then finally bringing myself here and posting... I think I just solved my problem.

I resized a case (RCBS F.L. this is 30-06 btw) and measured at the shoulder. 0.440"

I seated a bullet without any powder. Shoulder measurement is now 0.445".


I believe I had the seating die setup incorrectly. I put a trimmed case into the shell holder and raised the case. I screwed in the seating die until it contacted the case and backed it off a full turn.

I seated a bullet and the shoulder measurement stayed 0.440"

The round seats fine now with powder.

So I believe I was swelling the cases with the seating die by having it screwed in too tight.

what happened is the seating die will crimp when screwed down at the right depth, you had it screwed down too far and was overcrimping bulging the datum line. your fix was correct.
RR

thank you for the explanation!

Now that you have solved that problem, get yourself a neck sizer and you will be all set. I fireform everything, and then use a neck sizer only. Brass lasts a lot longer that way. Really no need to crimp on a bolt action.

Unless it is a rifle with substantial recoil. The rounds held in the magazine take quite a battering and can drive the bullet deeper into the case if they are not crimped.

I crimp on all cartridges with recoil equal to or greater than .375 H&H.

I also crimp .22 Hornet cartridges, but that is for consistent ignition only. The Hornet has such a thin case that it does not hold the bullet consistently. It has been my experience that crimping is the key to accuracy with the old Hornet.

I totally agree Big Uncle, I love the old Hornet. Those cases are like tin foil though, and you have to be sure that everything is aligned perfectly or you have a crushed case. I like WW296 for the Hornet. The 375 and the 458 got a heavy crimp on them. The single shot Rugers don't need it. I never seen any benefit from crimping the 270's or the 300's but the monster mashers do benefit from the crimp. I never crimped the 338's either.

I'm glad you got your problem solved. But I would hesitate on getting a neck sizer die. Especially if you're going to be using your ammo for hunting. That way you can be sure you will have no chambering issues if you need a quick follow up shot.

Yup when I read the initial posting I was sure of the answer as I did it myself once this year but the bulge was visible and I could also feel the swell. It's good you found the solution Streetdoctor.

To prove how tightly the case neck holds the bullet just borrow a inertia (hammer type) bullet puller and see how many raps on a block to even move the bullet are needed.

BTW folks how do I make up a signature that inserts on the bottom of my posts?