300 Win Mag reloading Problem

[Fallen Timber]

I’ve got a Rem 700 loading 212ELDX Using 73.2 grn of H1000 with an OAL of 3.610
Im fairly new to reloading and long range shooting. This is my first forum so I hope someone can help. This issue has stumped several seasoned shooters and two gunsmiths. I’m handloading NEW brass and the loads are shooting GREAT. I’m eating a piece of 17x24” steel at 1,000 which I’ve never done. My issue is that after the brass has been shot I’m depriming, cleaning, priming, full length sizing and re loading the rounds and the once shot rounds are not feeding into the gun. It is also in such a bind that it’s leaving noticeable scuffs on the projectile. I know I know. Need to trim them. I ordered my trimmer, but I’ve never trimmed in the past and always been able to get at least 2 shots without any issues out of the casings. Now all the sudden one side of my neck is noticeably longer than the other so my concentricity is off BIG TIME. Im not a gunsmith but have bought a scope and sent pics to gunsmith and other shooters and the lands looks good the chamber looks good. I’m obviously going to trim EVERY case from here out but what could have started this issue?

 

[Walt Krafft]

Do your once fired necks look bad before you resize them? If yes, your chamber is messed up/crooked to the bore. If they look good after shooting and bad after sizing, you have a sizing die problem.

 

[Zero333]

Scuff marks on the projectile usually mean they're in the lands.

But anyhow... Clean the bolt face. Make sure the ejector is not stuck (hook a piece of brass over the extractor and see if it moves the ejector plunger in and out of the bolt head)

You scoped the barrel, so I assume there is nothing inside the chamber that shouldn't be there. But it be a good idea to clean the barrel and chamber.

you can paint the cartridge with a marker, then chamber it and see exactly where things are interfering.

 

[10at6]

Not feeding or not chambering?

 

[Fallen Timber]

Not feeding or not chambering?

Chambering sorry

 

[Fallen Timber]

Scuff marks on the projectile usually mean they're in the lands.

But anyhow... Clean the bolt face. Make sure the ejector is not stuck (hook a piece of brass over the extractor and see if it moves the ejector plunger in and out of the bolt head)

You scoped the barrel, so I assume there is nothing inside the chamber that shouldn't be there. But it be a good idea to clean the barrel and chamber.

you can paint the cartridge with a marker, then chamber it and see exactly where things are interfering.

If you can see the scuffs are only on one side of the round, and the oal hasn’t changed I actually made one at 3.500 instead of 3.610 and same result. The bolt face looks good and can’t tell that there is an issue with the chamber

 

[Fallen Timber]

Do your once fired necks look bad before you resize them? If yes, your chamber is messed up/crooked to the bore. If they look good after shooting and bad after sizing, you have a sizing die problem.

I’m going to take some measurements and photos in the morning. It I’ve starred at them so much everything looks crooked now ‍

 

[46and2]

Do you have a concentricity gage? If the loaded round has an ungodly amount of run out you'll get that exact mark on the bullet.

The 'good news' the round is so banana shaped that the act of chambering straightens it out a bit.

 

[gman47564]

do you have a bore scope? you may have a bad carbon ring causing your issues...

 

[coldboreshot]

I’ve got a Rem 700 loading 212ELDX Using 73.2 grn of H1000 with an OAL of 3.610
Im fairly new to reloading and long range shooting. This is my first forum so I hope someone can help. This issue has stumped several seasoned shooters and two gunsmiths. I’m handloading NEW brass and the loads are shooting GREAT. I’m eating a piece of 17x24” steel at 1,000 which I’ve never done. My issue is that after the brass has been shot I’m depriming, cleaning, priming, full length sizing and re loading the rounds and the once shot rounds are not feeding into the gun. It is also in such a bind that it’s leaving noticeable scuffs on the projectile. I know I know. Need to trim them. I ordered my trimmer, but I’ve never trimmed in the past and always been able to get at least 2 shots without any issues out of the casings. Now all the sudden one side of my neck is noticeably longer than the other so my concentricity is off BIG TIME. Im not a gunsmith but have bought a scope and sent pics to gunsmith and other shooters and the lands looks good the chamber looks good. I’m obviously going to trim EVERY case from here out but what could have started this issue?

I'm trying to process everything your describing. I'm curious...what mfg brass are you using? During your F/L sizing (especially after the first "fire-forming"), are you now including a shoulder bump with the sizing? The one-side markings on the bullet could be related to how the round is feeding from the mag. (Too steep of an angle perhaps). It may not prevent the round from chambering but may cause some interference along the way. You definitely need to check your trim length but you might be experiencing brass expansion during the fire-forming. This happens to some brass and tight chambers where you need to pay attention to shoulder bump (setback). It only takes a minute amount, 1-2 thousandths.

 

[MikeT124]

You may also want to pick up a chamber length gauge from Brownells. It will tell you the exact length of your chamber, may help you to solve your problem or at least lead you to the cause. The gauge has you use the exact bullet your are loading so everything should be quite accurate.

Mike

 

[XTR]

Will it single feed a round if you start it into the chamber and close the bolt? Or is the problem only feeding from the magazine?
If it does, where is the scuffing? Is it on the projectile or the brass?

Have you measured your fired base to datum line on fired and sized brass?

 

[Sniper338]

You need to post more pictures... theres several thing it could be and everyone is touching on them. It hard to diagnose issues over the computer without very detailed post and pictures.

 

[LeeA]

I’ve got a Rem 700 loading 212ELDX Using 73.2 grn of H1000 with an OAL of 3.610
Im fairly new to reloading and long range shooting. This is my first forum so I hope someone can help. This issue has stumped several seasoned shooters and two gunsmiths. I’m handloading NEW brass and the loads are shooting GREAT. I’m eating a piece of 17x24” steel at 1,000 which I’ve never done. My issue is that after the brass has been shot I’m depriming, cleaning, priming, full length sizing and re loading the rounds and the once shot rounds are not feeding into the gun. It is also in such a bind that it’s leaving noticeable scuffs on the projectile. I know I know. Need to trim them. I ordered my trimmer, but I’ve never trimmed in the past and always been able to get at least 2 shots without any issues out of the casings. Now all the sudden one side of my neck is noticeably longer than the other so my concentricity is off BIG TIME. Im not a gunsmith but have bought a scope and sent pics to gunsmith and other shooters and the lands looks good the chamber looks good. I’m obviously going to trim EVERY case from here out but what could have started this issue?

Did you try chambering the full length sized cases before loading them?

 

[MagnumManiac]

Looks like a burr has been left at the start of the throat to me. Have seen it several times, some are too large to be worn away from normal cycling/firing and need a scotch bright treatment.
You will have to have the chamber/throat area borescoped to find the exact issue.

Cheers.

 

[Frankm]

Does a fired case chamber back into rifle easily? If so, you got either a sizing Die problem/adjustment issue OR something in throat/burr.

If it was a throat/burr issue I d think your first firing would also have issues.

My guess is sizing ....

 

[Crunchy21]

I had this same problem. Drove me nuts to figure it out. It was my sizing die needed to be backed out 1/4 turn. Bet $ that is your problem.

 

[Mr.Knowit all]

I’ve got a Rem 700 loading 212ELDX Using 73.2 grn of H1000 with an OAL of 3.610
Im fairly new to reloading and long range shooting. This is my first forum so I hope someone can help. This issue has stumped several seasoned shooters and two gunsmiths. I’m handloading NEW brass and the loads are shooting GREAT. I’m eating a piece of 17x24” steel at 1,000 which I’ve never done. My issue is that after the brass has been shot I’m depriming, cleaning, priming, full length sizing and re loading the rounds and the once shot rounds are not feeding into the gun. It is also in such a bind that it’s leaving noticeable scuffs on the projectile. I know I know. Need to trim them. I ordered my trimmer, but I’ve never trimmed in the past and always been able to get at least 2 shots without any issues out of the casings. Now all the sudden one side of my neck is noticeably longer than the other so my concentricity is off BIG TIME. Im not a gunsmith but have bought a scope and sent pics to gunsmith and other shooters and the lands looks good the chamber looks good. I’m obviously going to trim EVERY case from here out but what could have started this issue?

When I first started out I had a Steyr in a 300 and custom 300. No matter how I sized my brass the one would not want to chamber in the other. Looking back that was dumb to do but in theory the SAMI specs should have worked with each other at least been close and it was not. Since then if I have multiple rifles of the same caliber I keep the brass separated. Maybe your chamber is a bit off from your dies..just a little? Or you are sizing too far one way or the other? I even contacted Larry Wills and bought his Collet die for belted magnums. He may be able to help. Good luck?

 

[SWRichmond]

http://www.larrywillis.com/300winmag.html

Belted magnum collet resizing die.

Resizes the case body in the area forward of the belt, which is hard for a normal sizing die to do on a belted magnum case.

 

[gary0529]

http://www.larrywillis.com/300winmag.html

Belted magnum collet resizing die.

Resizes the case body in the area forward of the belt, which is hard for a normal sizing die to do on a belted magnum case.

+1 on this die
Had 100+ once fired 300WM cases-Norma
About 75% failed the"drop test" into the top of the die - ran those through the collet portion go the die and VOILA all chambered easily.
Did I like dropping $100 on the die--nope
Do I like rescuing and re-using $2 brass-youbetcha

if you don't have any of the other aforementioned problems, my bet is on increased case diameter just above the belt and Larry Willis' die should remedy it.

Gary