Set Back doesn't like old Load

[noload]

My barrel was 28", 1 1/4" straight, 8tw Krieger, 6br, 1700 rds. I sawed it off in stages, to get beyond the fire cracking. The result is a 23" barrel. The barrel used to like a load of ...RL15,29.8 w/105VLD touch. . I tried that in the shorter barrel to no avail, The new node seems to be the 4 tenths less powder, with everything else the same. I do not like the velocity change, but it is accurate. My question, is this the norm? I spiked it up to 30.2 RL15 it didn,t like that either. Maybe go a little hotter??? The barrel is real clean, and no copper in it yet, that I can see, like before I cleaned it well.. When the barrel was new, It kept gaining velocity till it got to about 1000 rds. I've only shot 45 -55 times testing.Maybe it will get faster as it gets dirty? I lost about 220 FPS. I thought a shorter stiff barrel would have wider nodes, now I have second thoughs. Maybe I'm too picky...got a new Benchmark coming this week anyway.

 

[Nomad47]

If you subscribe to Chris Long's OBT (Optimum Barrel Time) theory, you would expect to have to change the charge weight.

 

[jonbearman]

What about a powder charge,say varget.

 

[halfmoanut]

My experience has been this. I have set back 4 barrels all in the same caliber. 1 has given me the same accuracy with the same powder charge,same seating depth,same bullet, with a reduction in velocity, however it only lasted for 300 rounds and it quit shooting.2 of them would not shoot anything as well as when new. 1 has been shooting as well as new with a velocity loss and is currently at 400 plus rounds. Bottom line is this, nothing trumps accuracy,nothing. JMTC.

 

[noload]

Varget never proved quite as good as Rl15 to me. At least with a longer barrel, besides I just got a ton of RL I wana try to make work. I will try varget though. I do alot of F Class matches at 300Yds. I had to try this early (1700 rounds)set back thinking it would be my primary 300yd gun. It was its best when at 400-1200 rounds. A real Xmuncher. When it lost that I just had to try some expermenting, I though if I got back into some good meat on the barrel when it still had some life it might be good as new. Im trying to get that load before it falls off again, you know minimize the test time...we all try to do that. Time will tell how many rounds it will survive. I knew There would be a speed sacrifice going into this, now I know how much and how the groups compare to new. At this point it think it will hold a solid 15 shot group @ 1/2 moa @ 300.....maybe 2 out. I don't like to go to a match with less than that. I have a hand full of guns work ok but I aways seem to use the best one, and let the rest collect dust. This game never ends ...always looking for the Holy Grail.

 

[Steve Blair]

Bottom line is this, nothing trumps accuracy,nothing. JMTC.

[br]
So, you promote using the 6mm PPC in 1000 yard F-Open?

 

[FroggyOne2]

When you change one aspect of the formula, do you expect the formula to remain the same?

 

[Nomad47]

Bottom line is this, nothing trumps accuracy,nothing. JMTC.

[br]
So, you promote using the 6mm PPC in 1000 yard F-Open?

You're too funny, Steve.

 

[fredhorace77]

I dont know if this has been already mentioned but did you also try touching up the crown