RL-15 starting loads?

[okbob51]

I just bought a Savage 12 Benchrest with an 8 twist barrel. I picked-up a box of the Berger 105 Match VLDs. I have some Reloder 15 on hand and want to give it a try.....problem is: I don't know where to start with powder charges and OAL. Alliant has not published load data for the 6 BR. I'll be using new Lapua brass and CCI BR primers. Anyone shoot RE 15 in the 6BR?

 

[Varminator]

Start around 28 gr and work up from there. That should give you about 2650 to 2700fps and about 45000 psi. But the Lapua brass will handle upwards of 65000psi but the variables for barrels, fit of bullet and everything else can change that. Each barrel is slightly different. My one and only 6mmBR is a 10 twist and shoots the old 95 gr VLD with great results
but does not like the new ones as much as the 87gr VMax. Probably the max load will be in the zone of 30.5-30.8. I had great results with the 95 and 31.5 gr of RL-15 however with the 6Dashers I run with the 105 molys 31.5gr RL-15 mild and 33.5 hot.
Mark

 

[gemmellsc]

okbob51,

I load for my Dad with the same components and same gun. I'll look over our load data tonight and post if for you.

Bill

 

[cmillard]

get yourself a hornady lock n load oal gage. use the same bullet every time unless you switch bullts. but mark each different bullet so you dont lose track of the maker. this will help you with your seating. im sure, since it is a factory rifle, the oal will not be very long.

 

[expiper]

Hi okie Bob....the load data give is good (30-30.5gr) but the OAL is going to unique to YOUR chamber and its ammount of freebore....most load around 2.345 or longer and the optimum is with the bullet touching the lands and leaving a square to slightly longer than wide mark on the bullet.....Roger
PS...record that over all length ,,,buttt...it will change as the bbl. wears...you gotta chase the lands ,,,,withe every 100 rds the wear will be around .0015-.002 with a cut rifled .bbl...I just wanted to add to the post below....his rifle has a FB of .114" ...mine is .040" that is a diff of .074"...guess what...add .074 to 2.345 and "viola" you get 2.419"!!!!!! His measurements are exactly rite....you can see the diff in FB and how is is usefull....so if you know your FB you can do the math and be within a cupla thou. on OAL rite off the bat.....

 

[gemmellsc]

+1 on what expiper said.

I looked at my Dad's load data, and unfortunately he didn't write down the OAL from base to tip. He just has his Wilson micro-seater setting recorded. (This is why I preach to him about writing everything down! ). He also has no loaded rounds that I can reference for you either. Enough bashing him... ,and on to what works in my Savage 6BR... I beat the pants off him at our last shoot anyway! ;D

I will start by saying that MY SETUP IS TOTALLY DIFFERENT THAN YOURS AND YOU SHOULD ASSUME EVERYONE ELSES IS AS WELL... Enough with the disclaimers!

I have a Savage target action mated up to a McGowen barrel w/ minimal headspace on new Lapua brass. I "had" a 0.1147" freebore at time of install. I'm sure it's a little more now... I have a little over 400 rounds down the tube.

Here's my load data from the last "fun" match:

-Berger 105gr VLD Lot # 1770, these are the new "thick" version, or "target"

-Lapua brass, .002" neck tension, w/ CCI450s

-30.4grs of Varget (Don't have any load data for RL-15, but you're going to find they will be within a grain of one another ***start around 28gr as Varminator suggested and work up)

-Bullet seated to 1.8330" measured from base to ogive using a Stoney Point comparator. This puts me slightly in the lands when closing the bolt. I aim for about 0.015" in the lands.

***I have 7 loaded rounds left over from the match... I measured them for you, and here are the measurements. From base to tip they range from 2.4145-2.4195" (0.0050" variance), but they ALL measure EXACTLY 1.8330" from base to ogive. I point this out to demonstrate that measuring the base to tip dimension is not the way to go! Get a stoney point or the likes and never look back!

With this load I shot a 1.44" ten shot group at 300yds w/ no wind flags, a loose sand bag up front, and only my hand for support in the rear (rules of the fun match). The load shoots well in my gun, but if I were to try and make the base to tip dimension the same not only would it probably shoot all over the place, but it could be unsafe as well.

Hope this helps to get you started anyway.

Take Care,
Bill

 

[okbob51]

Thanks guys for the loads and tips! I've got some loaded to your spec's and now I just need to get out and shoot em. I started at 28.5 and went up to 30.5 in .5 increments. I'm overall at 2.411. I plan on buying the Hornady or Stony Point cartridge gauge.

 

[gemmellsc]

Good luck, and just a tid bit more info. When you get around 30grs you may want to load the remaining charges in .1 gr increments so you can watch for pressure signs. You'll probably find that your max lies somewhere between 30-31grs. Make sure that AS SOON as you see pressure signs that you DO NOT go any further! Also remember that RL-15 is a little more temp sensitive than Varget and that your max load in cold weather is going to be higher than in the summer time. I usually do all my brass prep work at home, seat my primers, and then I'll load both powder and bullet at the range. This really helps when you're trying to find the max, and then when you want to confirm what you thinks shoot best. If you are not set up to do this then just load up to about 31grs w/ .1 increments up from about 30grs, and stop when the pressure starts showing up. Take the remaining rounds and use a bullet puller (I use an RCBS that you tap on a hard surface). Remember you're dealing with a live round, and don't use any method that may set the round off.

Good luck,
Bill