Home Forums Reloading Big Game Rifles Jack O'Connor's load data

Keep in mind that O'Connor used WW brass, and a powder funnel with long drop tube, which required shaking and tapping as the powder trickled in. There is nothing magic about 62 gr. but it is pushing things and if you have a tight bore or chamber, soft brass, a bullet with a long bearing surface, min. headspace or any number of other things, you could be at max pressure during fall temps. If you shoot those same loads during the summer you may see some symptoms of high pressure, which to me = risky. If your primers fall out, or your bolt handle is sticking, you are way overpressure.

forepaw

He used this load back in the 40's...once IMR4350 cam out he used that and once H4831 became available that's about all he used from then on.

I have used 49.5 gr. 4064 in my .270 too. It's a good load and chronographs about the same speed as 60 gr. H4831, in my gun.

I am not and don't intend to be critical, so....

I used 49 grs 4064 TILL I found JOC's load. After getting my chrono I found these results to be pretty consistent.

49-4064 / 130 / 22" = 2900 fps.

62-4831 (MS) / 130 / 22" 3100 fps.

HOWEVER, HOWEVER - when MS ran out the NEWER H4831 did NOT equal the MS. Vels were @ +/- 3000. I quit H 4831 altogether when I found 7828.

NOW TO BE FAIR H changed their newer 4831 at least twice that I did NOT know about. JB (MD) says that now the newer H 4831 is performing pretty well. I would accept that sight unseen.