I have had at least twelve 270’s built with best quality barrels and fitted by really great rifle builders. In a 22” barrel I have never gotten to 2900 in any 22” barrel with any of the 4831’s made since 1985. I was one of the first to work with R26 and with that powder could reach 3000.
With 130’s I have had the best luck with IMR4831 over H4350, R17, R22, IMR7828ssc. I haven’t tried R16 or HUNTER yet.
I have had a 25” and a 26” built but both were cut to 23” then 22.5” then 22”. Those long barrels were quite clumsy.
Years ago on the Campfire, someone asked a question about what is the fastest load with a 220 grain bullet one could get out of a 270. That sort of caught my interest, so I took it to task to find an answer for that question. Looking at published load data and the pressure numbers listed, H 4831SC jumped out at me.... So with 200 and 220 grain bullets, I worked up some loads, as far as I could push them and posted what my chronographed reported as their velocities. I went beyond published load data, but had no problems with loosened primers... even after 10 shots on the same brass.
Needless to say, in Campfire fashion, I got flamed all over the map. It ran many pages in just a couple of days. And then per usual someone asked if I had pressure tested the loads.... Uh no, "my personal" pressure testing lab was down and in the shop.....
However, someone supported my work, and posted his phone number. So he immediately got flamed also, but when asked, he said yes he did have a pressure testing lab, and gave a phone number, with a 541 area code. Since I live in the same area code I called it. It was answered with, "Hello this is Nosler Bullets, how may I direct your call?". I asked for Mike, who had made the post supporting me ( and the ONLY one supporting my findings). We had a good conversation.
Mike simply stated, you can't get enough 4831sc in a 30/06 to exceed SAMMI specs. He also later posted that on the thread, which quickly died and went to page 3 then 4 then 10 real quick. He had received quite a few calls.
Fast forward, I asked him about the 270 also. He told me on any 06 based case, you can't get enough 4831 in a case to exceed SAAMI specs. IN a 270, I only shoot two bullets on a regular basis out of my Model 70 in 270. The 140 grain Ballistic Tip and the 160 gr SMP Partition.....the latter I push to max velocity, just like a do the 220 SMP out of the 06.
So in both, I've load enough 4831 and also 4831sc, that if not crimped as the powder expands it will push the bullet out of the case. So I crimped them, a roll crimp worked just fine, but I did pick up a 270 crimp die from Lee...
IIRC, in both instances, my max loads were about 200 to 250 fps MORE than max loads were listed in load data manuals.
Didn't experience any loose primer pockets, when rounds were reloaded more than 10 times. Do people really need the extra velocity? probably not, but with those bullets I decided if it was there, I'd use it.. especially with the partitions.
This was results from someone who normally just uses IMR 4064 or 30 grains of IMR 4198 as hunting loads with his 270s, and 140 gr Ballistic Tips...either that will work just fine to 250 yds or more on any Deer that ever walked.
But if ya 'want it all' out of a 270, H4831 or H4831sc would be your best powder choice.
oh and that Mike at Nosler? At the time, he was their head ballistician ... Take that with how ever many grains of salt ya want to....
