I have a question. I have an 6.8 upper that has been exhibiting overgassing, and I was told to put an adjustable gas block on it. I am having a hard time finding a setting that will allow me to use both the SSA 110gr ProHunter and 115gr SMK loads w/o destroying the brass for reloading.
So far I have only been able to tune it for one bullet weight; if I try the other, the brass shows major swipes and extractor marking, making it difficult to reuse for reloading.
My plan had been to practice with the 110gr loads and reload them, as these loads seem to be more accurate in my rifle, and then use the 115gr SMK loads for home defense, etc. The point of impact at sub-50 yards is very close.
But now it seems that I may have to stick with the ProHunters since they are more accurate and cheaper to reload. I would still use the SSA 110gr ProHunter factory rounds for defense.
My dilemma is this: I’m under the impression that the ProHunters may exhibit excessive penetration, especially since I’m using the Tactical loads. 15+ inches of penetration might be a tad too much…and possibly more with the Tactical loads.
Thank you. I had been under the impression that the penetration might be a bit too much.
I’ll simplify my life and just stick with the ProHunters then, and sell off the 115gr SMKs then - if I adjust the gas block so that the ProHunters work perfectly, the SMKs don’t cycle reliably plus the brass is ruined.
With all the 6.8 mm uppers we have used since 2002, none have ever required an adjustable gas block or would not function with both Pro Hunters and 110/115 gr OTM’s…
Apparently the builder of this upper decided to make the gas port larger to accommodate the shooters who were complaining that the SSA 90gr loads were not cycling the action. Then SSA decided to up the powder charge or something… So the upper was overgassed, and even with a SSS spring and H2 buffer it was bending case rims and having major swipes/extractor gouging of the case head.
Since the builder has more or less gone out of business, and isn’t answering emails - his phone number is no longer on his website - I had to do something to get my expensive upper to run.
It was that or sell off all my 6.8 stuff at a large loss. I’m on my 3rd upper that hasn’t met expectations, and I won’t buy a 4th one. I like the round, but am kind of tired of the hassles I’ve been encountering with it.
I’ve used standard carbine, H1, H2 buffer, standard carbine spring, and Tubbs SSS spring. None helped all that much.
I can get the gas block tuned to one load, no problem. It’s when I try to use both with the same setting that I run into problems. Seems like I haven’t been able to find a compromise setting that will cycle both rounds and doesn’t destroy the brass.
Looks like I am pretty much hosed. This appears to be one of the darker sides of the 6.8 round - there is such a range of projectiles, that one gas port size may not accommodate them all. What works for 110-115gr loads doesn’t work well for the 90gr crowd, and in reverse.
I’ve got a one load gun, and will have to readjust the gas block to change loads out, plus rezero…
We have been able to shoot numerous rounds of Hornady 110 gr OTM and 110 gr VMAX, the SSA 115 gr OTM, 110 gr JSP, 110 gr TSX, 110 gr Accubond, 100 gr Accubond, and 85 gr TSX; Rem 115 gr OTM and 115 gr JSP through various 6.8 mm uppers without any functioning issues. We recently ran a test of the new Battle Comp muzzle brake on 12" and 16" 6.8 mm uppers assembled by Wes Grant at MSTN and had NO difficulties in rapid fire with six different loads from 4 different ammo vendors…
I know ADCO offers a service where they can relocate gas ports. This obviously would have to entail filling/welding the original port.
Perhaps they could weld your exising port and re-drill it smaller, I just don’t know if this is an option or not. Just a thought, if you think the barrel is useless now it might be worth a shot.
Well I won’t say the barrel is useless, it’s just much more of a hassle to switch ammo than say with the 5.56, which runs fine with everything I feed it (55gr FMJ to 75gr Hornady TAP) w/o issues.
It’s quite accurate, and until I have a pressing need to use more ammo types than the Prohunters, I guess I’ll stick with it.
Not sure about redrilling a new gas port in the same place, but it wouldn’t hurt to ask about that just for my info.
As I noted above, over the past 8 years, our numerous 6.8 mm uppers with 8" to 20" barrels have worked with loads from 85 gr to 115 gr without any problems.
I agree, and I’ve been looking into getting it rebarrelled, but am running into problems… I don’t want to sell the upper and wait forever for a Noveske either.
