Concentric Rounds

Vince · Feb 24, 2014

Starting to get back to my old self.

I went shooting this morning, having given up on IMR 4350 for the .338 Win Mag with a 250 Grain Hornady bullet, so I'm working up a load using IMR 7828. Nothing to write home about today as my best group was in the 1.5" range. What I did learn however was that the rifle seems to prefer powder charges less than mid-range. I worked up some more loads tonight from the midpoint back to almost the starting load. I'm in hopes I can get out next week to shoot them.

What amazed me tonight was the concentricity of my rounds when I put them on my Hornady Concentricity Guage. No round, of fifteen loaded, had more than 0.001" of runout. Either I messed up somewhere or my technique has gotten a lot better. If the latter, and I suspect it is, I'd like to thank Guy for mentioning the 1/3 of a turn trick in one of these threads.

Now if I can't get these Hornady 250 grain bullets to shoot I'll move on to the 200 grain AccuBond. Heck, I'll be working up the 200 grain Accubonds too but I'd like to get these Hornady SP's to shoot. If this powder don't do the trick I'll try H4831 or IMR 4831. :grin:

Thank you Guy. Reading your post in here has helped me a bunch.

Vince

DrMike · Feb 25, 2014

You're moving in the right direction. Turning out consistent ammunition is not difficult; it just requires attention to detail.

kraky · Feb 25, 2014

I have both the hornady unit and a rcbs. About 20% of the time they measure fairly equally. 80% of the time the hornady unit measures about 1/3 the run out of the rcbs.
The big argument is which unit more accurately reflects how a casing lays in a rifle chamber...keeping in mind some chamber dimensions are fairly loose....the holding of the rim by the bolt face...etc etc. Perhaps neither unit does.
Fotis here has been using the hornady unit with great success....in other forums its the devils doings. Lol.
Bottom line though is if you've got a measurable improvement you HAVE to be heading in the right direction.

cloverleaf · Feb 25, 2014

OK, "1/3 of a turn...." ? Enlighten me. CL

RiverRider · Feb 25, 2014

Me too!

Guy Miner · Feb 25, 2014

Vince - I think someone else mentioned that 1/3 of a turn thing.

I'm not that convinced about it.

Instead, I use really nice seating dies, to seat the dad-gum bullet straight.

Regards, Guy