IMR's XBR8208 in an AR10

[KYbulldog]

Anyone having good success with this powder in their gas gun?
May have had some short stroking issues with it using comparable loads to RL15 and Varget. My highly reliable AR10 that has shot all good commercial and hand loads so far, hiccuped today with the XBR.

 

[KNIGHT11B4]

Im running it in my JP LRP-07, 16inch 308.

Haven't done extensive testing but I developed a load using it and a bunch of 168 amax that I had. Functions well and accuracy is great.

 

[steelringer]

Same here, in my 14.7" pinned .308 it runs very well with 178 amax's.

 

[Black-X]

Played with it a little in a .308 LRP-07 as well and it functioned fine with 155 AMAX bullets. I'm now using it in a KAC SR-15 e3 Mod 1 right now with 75gr Prvi bullets and it has been working very well out to 600yds (no hiccups yet either).

 

[AZIROC]

I have an ar in 308 *dpms pattern* but use xbr with my 168 smks and amaxs and it loves it .

 

[robinzon]

I have an ar in 308 *dpms pattern* but use xbr with my 168 smks and amaxs and it loves it .

Hello, new to the forum but have been reading around for a while... at any rate, I just got an Armalite AR-10 in 16" (used). I love 8208 in my Savage 10TR (LE only bull barrel).

I used 42gr of 8208 with 175gr Pulled SMKs in the Savage w/o any issues. However, when I used it to function test the Armalite the brass has a number of longitudinal scrape marks all around and one of the casings has extractor damage on the rim. I am not sure if 8208 is a bit too fast for the rifle and is creating excessive pressures??! From what I read people are having better luck with 155gr SMKs and different powders such as IMR4895.

 

[robinzon]

Anyone having good success with this powder in their gas gun?
May have had some short stroking issues with it using comparable loads to RL15 and Varget. My highly reliable AR10 that has shot all good commercial and hand loads so far, hiccuped today with the XBR.

BTW: I did not have any Short Stroking with the 42gr 8208 and 175SMK load whatsoever. No problems with feeding, etc. just that the brass seems to be roughed up with the scrapes/extractor. What OAL are you seating these to and what is your Case Trim length, I go to about 2.009 to 2.0012 or so. I really think that 8208 is a bit too slow burning and creating excess pressures for the
Semi-Auto. Perhaps a faster powder would work better, ie IMR4895 or 4064 (people had decent results).

INCINDENTLY, my SCAR 17S Heavy has absolutely NOOO problems shooting this load and is very VERY accurate.

I think this is particular to the Armalite perhaps as you are having these issues and while I do not short stroke, there are signs of high pressure.

 

[KYbulldog]

I don't think its the gun. I think its me. Unfortunately this happened toward the end of the range time and I didn't have any more cartridges loaded with the xbr to try and narrow it down. Too many other variables possible plus recent change to an adjustable gas block and having tuned it to commercial loads probably is the culprit. (start low work up…didn't think to open up the gas block to compensate) I did look at what online data is available for XBR and noticed against Varget and others that XBR appears to give lower velocity but higher pressures. ?? Not what I want for my 18.5" gasser. Thanks all for the replys!