This is an interesting problem that I ran into with the .30 FX barrel kit on my MKII. I normally torque down my barrel's set screw by feel to a certain point after cleaning it. When I was benchmarking my configuration, my barrel unseated and moved forward just under an inch from the block. After realizing this, I torqued it down a little more than usual, and after a while it popped out again.
Finally, I got to a point where it stayed put. I just made a mental note about it and carried on. When I removed the barrel, the forward o-ring on the brass inlet was nicked. I replaced it with another, but it felt as if it were raised higher than the breech-side inlet o-ring. Sure enough, I WARPED the stainless piece that the set screw clamps down on! It's toast, and I need another one now.
I modified a TJ barrel from a blank for my MKII. Originally, I had it sitting nice a tight in the block, but then I wound up removing just a tad more material on my lathe to make it the same size as the FX barrel kit. Sure enough, the barrel pops right on out when the power is turned up as soon as it gets somewhere north if 115FPE).
I'm starting to debate on how to fix this issue. It coincided with the colder weather here, which makes sense. I decided to keep my MKII in 25 cal, but even then - it's shooting over 100FPE and I suspect that this is going to be a common theme if I don't do something about it. I'm not real excited about the prospect of notching a dimple in the side of the barrel for harmonics and possible damage. I could try larger, drier o-rings, but that could be a nightmare.
Anyone have thoughts on this?
Finally, I got to a point where it stayed put. I just made a mental note about it and carried on. When I removed the barrel, the forward o-ring on the brass inlet was nicked. I replaced it with another, but it felt as if it were raised higher than the breech-side inlet o-ring. Sure enough, I WARPED the stainless piece that the set screw clamps down on! It's toast, and I need another one now.
I modified a TJ barrel from a blank for my MKII. Originally, I had it sitting nice a tight in the block, but then I wound up removing just a tad more material on my lathe to make it the same size as the FX barrel kit. Sure enough, the barrel pops right on out when the power is turned up as soon as it gets somewhere north if 115FPE).
I'm starting to debate on how to fix this issue. It coincided with the colder weather here, which makes sense. I decided to keep my MKII in 25 cal, but even then - it's shooting over 100FPE and I suspect that this is going to be a common theme if I don't do something about it. I'm not real excited about the prospect of notching a dimple in the side of the barrel for harmonics and possible damage. I could try larger, drier o-rings, but that could be a nightmare.
Anyone have thoughts on this?