Roy,
Tell us about the 4000-mr and 7828 loads you're running in a stock 270. I just got my 721 a new 270 barrel and I'd like to try some other/new things. I've got the standby h4831 and some RL-17 to try, but I'd like to try something else.
I'm kind of a funny ol' fella with a great respect for the 270 Win. We've had a good nearly 50 year relationship with it.
I feel the ol' Winny was made for around 3100 FPS with the 130/140 offerings. Any more than that and a fella ought to get one of them there magnums.
In the late '60s I discovered, after I purchased the original paper sheet Oehler, that 4831 wouldn't get the Sierra 130 GameKing near 3000 with a 24" Douglas premium barrel.
Tried Norma 205 and found that I could get that bullet to much faster than is practicable and stopped at 3190 FPS. As 270 Win shouldn't have to shoot that fast..:roll eyes:
When N-205 went east with the geese I switched to 4350 and loaded to the same velocity, 3190. Pressure was notably higher but still with in reason, on the high side....
37 years of that load and the barrel went south. Installed a 27" Lilja.
Started with RL-22. Easily achieved the 3190 with any 130 and 140 offering. All shot great. Some shot greater than others.
Got the long range bug and started stoking her up a bit.
7828ssc took her well beyond 3300 with no complications other a feeling of disrespect for the ol' girl. Loaded back to 3190.
PP 4000 MR arrived on the scene. Gave her a go. Went clear up to 3350 with no noticeable complications. Note that my noticeable complications may be a bit different than yours. Livable for me is slight bolt lift with a click at the top of bolt lift on a Rem 700/721 action. A very faint extractor mark may appear. However, when that extractor mark is shined by bolt opening things are getting up there a bit too much.
It takes less 4000 than 7828ssc for the same velocity. Accuracy is as good and pressures "seems" lower.
My cheap chrony says 3235 FPS 12' from the muzzle. Shooter shows drops to 1100 spot on with an input velocity of 3180. "Spot on" means good enough to hit a 1 MOA gong at various ranges out to 1100 (when the wind ain't blowing too much
)
Actual loads:
140 Berger VLD (277140) - 54.9 gr - PP 4000 MR - Base to Ogive = 3.851" (using Sinclair nut) MV= 3190/3184/3156 @ 12'. 200 yard group - 0.33 MOA CTC.
55.5 gr 4000 with the above bullet = 3241/3244/3249 FPS and 0.19 MOA group @ 300 yards. Again this is simply too fast for my taste in the ol' girl so I've backed off to the the 54.9 grain load.
140 Berger VLD (277140) - 59 gr 7828ssc (assumed 7828 slower than 4831 - Notably WRONG) 59 grains of it = 3355/3378/3366. 200 yd group = 0.50 MOA
This rig is built on a 1908 Mauser action and has been as honest as the day is long since 1967.
I don't shoot heavier than 140 offerings as they have brought down everything that they have shot at from chucks though yotes, deer, elk and moose. None of these long range as I would with the 270 Allen Mag.....
Run the numbers and you'll see that the 270 Win ain't no slouch.....
Hope this helps.