311 or 312 bullets

[gerry303ca]

The .312 Hornady 174 gr work best in most of my .303B rifles, particularly in my Ross. I have the Lee mold but haven't been able to find the right load. What powder works best with cast?

[gunner]

That depends on what you will shoot, i mean the distance. If you would have good rounds only for 100 yards shooting try the TrailBoss. If they should have to work out to 300yards try a VV N140 or other slow burning powders. Fast burning powders will lead to a bunching of the bullet and smear the grooves with lead. Look at the reloading manuals of the powder makers.

[smellie]

I have published my test loads several times, but I will do so again... and explain.

With the Sierra 180 Pro-Hunter flatbase I am shooting 37 to 38 grains of 4895. Seating is to the OAL of a Mark VII Ball round. Yes, this crowds the leade just a bit, but it works. I shoot the flatbase because Enfield rifling likes it. I shoot the American bullets because they have relatively soft jackets and obturate well; also, they are extremely consistent. Velocity with this load is about 2250 ft/sec from the SMLE, about 100 ft/sec faster with the Ross. This velocity, 2250 ft/sec, was proven by test in 1910 to be the most accurate velocity with the 174-grain bullets then coming into use. With this load, I could get half an inch with a really good Lee-Enfield, an inch with a good one and less than the half-inch with a really good Ross. I say "could" because I no longer can hold a rifle steady enough to do this, even with sandbags and a rest.

With the Hornady flatbase 150 Spire Point .312, I find that satisfactory accuracy may be obtained with 40 grains of 4064, seated so the entire bullet cannelure shows. I have had 1-ragged-hole 6-round groups from scoped rifles with this loading, at 100 yards.

BTW, .312" was regarded as the upper limit of tolerance with the Mark VII bullet, but actual tests showed that it shot better than smaller-diameter bullets every time.

Hope this helps.

Good luck in the match.
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