338-300 ultra / 338 edge brass issues

[JMUPT]

I picked up a 338-300 ultra a while ago and haven't gotten around to shooting it until recently. The rifle came with 15 pieces of 300 ultra mag brass and 100 pieces of new 338 edge Bertram brass. I loaded up the ultra mag brass and had no issues, but when I went to load the bertram brass the round had a stiff bolt close. So I looked at the brass and noticed the bertram brass was a little longer in the neck than the ultra mag brass so I trimed it to the same length. Well I guess I should have looked at the brass a little better, because it is still hard to chamber and close the bolt. Looking at the shoulder area the bertram brass seems to have a rounded shoulder compared to the ultra mag brass. I think this may be my issue. I tried setting up my sizing die to push the shoulder back to see if that would help, but my shell holder bottoms out on my die before the shoulder gets pushed back enough. So my question is what should I do next, just go with ultra mag brass, or what can I do to change the angle of the shoulder on the bertram brass.

 

[JMUPT]

Picture of the brass the 2 on the left are the ultra mag brass and the 3 on the right are Bertram brass.

 

[IdahoCTD]

Paint the case up with a Sharpie and see where it rubs. It seems like mine were the same way until I FL sized and fired them. If nothing else you can have someone take some off of the bottom of your die.

 

[bayedup7]

Most chambers I have delt with this is the case. No big deal the shoulders need bumped back and neck trimmed on Virgin brass. Shoulder will sharpen up on firing. After bumping and trimming Virgin brass load development should go smooth

 

[HuntnID]

I believe the necks on the Bertram brass are slightly thicker which could contribute to the issue. I believe I had to get a .364 bushing up from a .361 for my dies....if I recall correctly.

 

[LoneTraveler]

Will empty Bertram brass, Full length sized and trimmed, Fit in the chamber and the bolt close easy? If the neck was longer on the Bertram brass and your seating die has crimping capability, and was set to not crimp on the Ultra case, The longer neck Bertram brass would hit the crimping shoulder in the die. And the bullet does not have a crimping grove for the edge of the case neck to crimp into. This will make a lump on the body of the case where it meets the shoulder angle. The case will go in the gun very tight and the bolt will turn stiff or not at all. Worth checking.

 

[JMUPT]

No the Bertram brass will not close easily, after sizing and trimming the necks. I have turned the die down as far as it will go and the brass will not chamber easliy. The outside of the Bertram neck measures .361 and the fired ultra mag brass measures .368 so since the bertram brass is chambering hard with out a bullet in it and the the brass is smaller thats not the issue at this time, maybe different once it's loaded.

Ok so here is a pic of the ultra mag brass measured with the hornady headspace gauge.
http://i808.photobucket.com/albums/zz5/JMUPT/IMG_20150905_090617_zpsxe9anaxa.jpg

Here is the Bertram brass
http://i808.photobucket.com/albums/zz5/JMUPT/IMG_20150905_090643_zpsrc4wezpk.jpg

Here is a pic of the case that I colored and chambered.
http://i808.photobucket.com/albums/zz5/JMUPT/IMG_20150905_125129_zpsqff6jtws.jpg

I have measured the diameter of both cases with calipers at the base of the case and at the shoulder and they are the same or the bertram brass is a little smaller. Let me know what you think.

 

[J E Custom]

A little trick to sizing a case a little more, when the dies are bottomed out it to place a feeler Gauge
between the shell holder and the case head. (Start with .002 thousandths and go up until the case chambers) this is a good way to bump the shoulder without changing your dies if that is what it needs.

Another thing to check is mic, the neck of a fired case and then the neck of a loaded case, the OD of the loaded case neck should be .004 to .006 smaller than the OD of the fired case neck.

J E CUSTOM

 

[R.Morehouse]

Feeler Gauge.........Great Tip......Thanks For Sharing....gun).....................