It would be insightful to test my loads, in my rifle, with pressure testing equipment.
We all know each rifle is an entitiy unto itself. Mine is a Rem factory varmint barrel. Typical long throat. Add in moly, roomy Win brass, and a bullet seated out long, but still off the lands.
I've been shooting this load for a few years now, since RL17 came on the market. Put a few thousand of them through the rifle without any typical pressure signs. Brass has been reloaded probably 20+ times and still in fine shape.
Before RL17, I loaded with RL15. Using RL15 and the moly'd 208 AMax, velocity topped out at about 2500 fps before I would begin to see some slight ejector swipe.
I've found RL17 is a game-changer in the 308, with heavies. Of course if one has a tight chamber, short throat, heavy brass, short oal, and nekkid bullets, the results will no doubt be different.
From what I gather, the F/TR competitiors have been going to the heavies of late, with their 30-32 " barrels they are seeing velocities over 2700 fps.
The heaviest bullet I've loaded in the 308 is the Hornady 225gr BTHP. It too shoots very well from my Rem barrel.
The powders and bullets we have today have extended the performance/range of most all the common chamberings. The 308 is no exception, but most folks prefer a bigger case. I enjoy the challenge of the 308 Win.
Well, I looked back at my old thread on the 215s. I only had 20 bullets to play with and didn't get past the 100 yard distance.
The 215s were stable at 100 yards in a 20.5" barrel, 1/12, 2500 fps. And also in the 26" bbl, 1/12, 2600 fps.
This was at 4500' el.
JBM calculator tells me the bullet is at the bottom of 'marginal' stability. It may have wobbled off in denser atmosphere. I can't give you any long range feedback on the 215 Berger from the 1/12 twist 308.
I did shoot the 225gr Hornady BTHP out to 1200 yards with good stability and accuracy. That was at 2500 fps, from the same 1/12 bbl.
Bottom line, I think 1/12 is really pushing it with the 210gr+ stuff at 308 speeds, but I've gotten away with it in local atmo 4500', and down to 2900' up in Glasgow MT country.
I'd feel a lot better with a 1/10 twist barrel, and that's the route I'll go if I can ever wear out these darn factory pipes.....smile.
With the 225gn hornady's do you think you could make consistant cold bore shots at 1000+ yds from day to day or month to month?
It's my opinion and experience that any well built rifle barrel fit properly to a receiver will shoot just as accurate starting with the first one from a cold barrel to the last of a 30 shot string with shots fired every 30 seconds. At most, the last 25 may center at the longer ranges 1/4 to 1/3 MOA above the first 5. But that's due to powder fouling causing higher muzzle velocities, not barrel temperatures.
I dont disagree with you on that Bart. Its just im my experience the 308 is very easily affected by environental conditions at ranges approching 1000 yds. I was curious if the 225gn pills are moving fast enough that they provide the consistency to get a first round hit at extended ranges, without having to walk them in.