30 BR new rifle please advice

[londonhunter]

Hi to all

I have been here seeking for advice for some time. After 02 years I finally received by first BR rifle.

I MUST stress I am NOT a benchrest shooter but have always admired the skilled and knowledge on this forum. I need some help.

Here we go.

The rifle is a tubegun I intend to use it for F Class or McQueens at Bisley in England.

It's a multishot 30BR. reamer is from PAcific Tools 30 Rabinett specification with a 330 neck.

Bluerprinted remington action with a lilja 1 in 15 twist.

My gunsmith did all the initial preps and made me 16 cases.

he started off with 6mm Norma cases which I have a surplus. After a week he discovered that there is 5 grain less capacity as compared to 6mm lapua cases

On his second attempt he used a RCBS mandrel and necked the lub cases to 30 caliber in one pass.

Then firefored the cases with cheap sierra 125 grain projectiles.

I understand he used load data from 6mmBR.com

i.e. H4198 and 34.5 grain of powder seating 0.005 short of the lands to reduce pressure for first firering.

When I recieved the rifle last week used these very SAME cases and started to reload.

Problem 1

I am struggling to get 34.5 grain of powder into the case.

These cases have NOT been trimmed and have been fired only twice previously - standard lapua 6BR brass.

I then changed to a long drop tube and even a tried folding a peice of A4 paper (21.9 inches as compared to american letter format) so I am dropping from about 18 inches in height with extreme caution.

The best I can get is the powder settleling is half way up the neck.

I tried 02 different tubs of powder with 02 different batch numbers and got the same result.

I have not measured the water capacity.

May be this is the next step but the over fill is SIGNIGICANT not a little bit.

I even checked the calibration of my RCBS chargemaster and crossed checked using a mechanical scale to check my charge weight

Problem 2

I used the best setteld powder case and proceed to seat a projectile

This is how how I calculate the neck bushing.

Cases have very uniform neck thicnkness of 0.009 inches all round

Porjectile is 0.3075 in diameter.

0.0090 wall thickness
0.0090 wall thickness
0.3075 projectile
0.3255 TOTAL

I started with 0.325 bush then proceeded to 0.324 hoping this will give me enough grip

I use wilson dies and seaters.

When I withdraw the top of the seater die the vacum sucked the bullet out with the top with withdrawing and there is so much resistance on compression the top rebounced back up!

Obviously this is completely wrong. Can somebody advice my next step

I live in London england and my gunsmith is in scotland.

I really feel like an idiot making some fundemental mistakes

I have gone over my step many many times but cannot see where I am going wrong.

There must be a lot of bench rest shooter out there using 30BR.
Can you advice ?

A shooter friend without 30BR experience suggested a high neck tension. What do you guys think? 323 322 ? What is enough

I can post pictures if it helps

 

[mkihne]

I use Lapua brass, not Norma, but assuming that case capacity is not that different, with Lapua brass 34.5 gr H4198 will fill your case well up the neck. Pretty standard for 30 br and H4198. That load may be near tops, not knowing your specs and you might start at or below 33 gr. as 30 br should have two or more accuracy nodes in that range. Necks plenty thin for Robinette reamer if specs at 330. 30 brs usually like higher neck tension and this will help you with a compressed load. Would start with 324 and likely go to 323 bushing to see if this tightens your groups. With 9 thou necks you could probably go to 322. Good Luck.

 

[ALO]

Hi London. I have been shooting a 30BR for a couple of years and yes you might want to increase the nexk tension by .001 or two. Now your powder problem! It is not written in stone that you have to use 34+ grains of powder. I use only 32.7 grains of H-4198, 205M Fed Primers and shoot Randy's 118 grain bullets. This fills the case about half way up the neck and plenty of room to seat the bullets. This load shot a .982 group at 500 yards at a competition here in Pennsylvania. Now this load also seems to work with the 110 grain Berger flat bases bullets also. Although they are not as accurate as Randy Robinett's bullets they are a force to be reckoned with. You rifle with a 1-15 inch twist may require a little bit more tweeking, but you will eventually get it to shoot. So get on out there and try different powder weights in that new rifle of yours. Start at about 33.0 grains and go to 33.4 grains. I've also heard that Vit 135 powder is also a good powder to use. I haven't played around with that because I've been pretty successful with H-4198. Good Luck!

 

[ALO]

Sorry LOndon, that was 32.0 grains to 33.4 grains.