Home Forums Hunting & Shooting Ask The Gunwriters FL resizing / shoulder bump not needed

I am beginning to hand load for my 7 PRC. It has a Bartlein barrel that was chambered by my gunsmith using his custom reamer. It shoots the Hornady factory 175 gr ELD X very well, but I am wanting to try the 180 gr Scenars!

My goal is to load precise ammunition and be very consistent.

I bought a Wilson micrometer seater, Lee neck collet die ( getting .002 tension ) and a Redding body die.

When comparing the 1x fired brass and the loaded factory ammunition, I am not getting any difference in the shoulder. Maybe .001 if I really try. Do I want to resize the body, but leave the shoulder alone?

Won’t the shoulder move if I resize the body?

Thinking about neck sizing only and after the 2nd firing start using the body die and move the shoulder back .001” ?

It chambers the 1x fired case as is.

Just me and you’ll get a bunch of opinions but I bump .002 each time I load. I want my case to feed, feel and align itself the same way from the start to the end of its life.

I use the " Wheeler" method i dont want any resistance when I close the bolt. Without a stripped bolt it gives you a false feel. Not always does .002 give you no resistance, Eric Cortina has a good video on it to showing how the bolt won't drop on .002 bump but will with .003.
If you go to Wheeler Accuracy I believe Alex's video is on his website.

If I bump now, won't I be moving the shoulder below virgin brass?

Factory ammunition is designed to fit 99% of the rifles its used in means undersized. If getting only 1 thou difference between 1x and factory then I figure it didn’t blow out completely. How you cure it is up to you, but I know how I would roll.

Well, thinking false shoulder or base the bump off the 2nd firing, which has worked in the past. I have always neck sized only every other firing but I am striving for better uniformity in my hand loads so wanting to FL resize every round. My hand loads may end up being warmer than factory. We shall see but have no intention of exceeding published velocity.

This being a custom, the chamber is probably on the tight side. I don’t think the issue is with mild factory loads.

FWIW using a Lee Collet die, properly set up, I have found no need to "bump" shoulders at all, even after cases have been reloaded many times. I only neck size, and I have batches of brass which have had dozens of load cycles without ever being FL sized or "bumped".

The brass case that comes out of the chamber after firing is always slightly smaller than the chamber, by reason of recovery of the elastic component of strain. It can't be bigger.

The only reasons a case might not go back into the chamber easily are either that it has expanded unevenly (such as due to sitting to one side or the bottom of a very oversize chamber, and ending up out-of round), or because of something you did to it in reloading, such as squeezing the body (and thereby pushing the shoulder forward).

Yes you will. Generally you won’t fully form cases on the first firing.

It often takes more than one firing to get complete fire-form. Additionally, brass will "rebound" to some degree to their former size. Use the above described method proposed by Erik Cortina, and you'll be fun.

I’ve had my best luck using Mule Deer’s methodology ensuring a straight, concentric case while fl sizing. It works for me.

I decap with a Lee decapping die.

I then fl resize with the decapper removed. Cases come out perfectly concentric, assuming the neck thickness is consistent of course. If not, turn the necks beforehand.

I now have fl resized cases. I now screw in the decapping unit back into the die…only a couple or three turns. The decapping rod is now “wiggly”, not turned down tight. I’ll run the fl sized cases back into the die only to the extent the case neck rides over the button and back down. The rod, being “loose” will follow the concentric neck of the brass and not pull it off center. I use case lube on every neck for consistency.

I shoot little bitty groups and do not have to worry about a slightly stiff bolt lift.


I’ve used Lee collet dies and have noticed I had to totally fl resize about every second or third firing…your mileage may vary.

Neck size until it needs bumping; if you're going to use the reloaded rounds for hunting, just cycle all the rounds through the gun.

Unless the gun is a superdooperprecsionpooper, as long as it fits & is concentric, it will work as well as doing anything more elaborate to it.

Opinions are like azz holes.............so take it for what it's worth.

MM

^^^^ This

Same here ^^^^

Agree with the above. I don't work brass anymore than I have to. As long as it chambers with minimal resistance it just gets run through a LCD.

When reloading I neck size all my cartridges, and all of my brass is rifle specific. If a cartridge come out of a chamber, it always seems to go back in.

That's the way I roll as well.

+1

No. As you screw the body die down, you will start to size the case body, which causes the case to elongate. As you continue screwing the die down, the case will continue to elongate even longer than the chamber length until the shoulder of the die contacts the shoulder of the case. Keep screwing the body die down until the stripped bolt just closes with no resistance, which is usually about 0.0025" bump compared to a fired case, IME.

Good suggestion. I always shoot for a .002” shoulder bump as well. I get that with a Fl sizing die, set to pfl size. That’s just how I do it, but I like to keep things simple

Thanks all for the sound suggestions. My goal is consistency from round to round.

Depends if I'm sizing for my comp guns or hunting rounds. On my comp guns that I chamber myself, I have a reamer spec'ed .002" under my chambering reamer at the shoulder and .003 at the web. I use this reamer to make my sizing die. I set it up for neck bushings. I do use new brass at each shoot, so the brass taken to the match will be used approx 8 times each. I make a gizzy tool as I call it to check the growth of headspace. It is a piece of barrel with the reamer run into it in order that the base of the case protrudes out of it. I use this to determine headspace. I take a fireformed piece of brass, decapped, and then measure from the base to the length of the gizzy. As the match precedes I check the measurements. At that time I will bump if needed. Never more than .002.
For my hunting rifles I use Redding dies. I neck size as I am not a person that lives at the range throwing bullets down range. 20 rounds of hunting brass will be all I ever need.