I tried 4 different powders with some 105gr hpbt. Minute of pie plate was normal.

Dropped down to 100SPBT and getting moa groups (with I4350)

I don't have any flat base 105's to try.

This is a 1970's Rem 700V.

I was shooting my heavy barreled Savage ($360 from Dicks) It really likes the 87 gr. Vmax with 45gr. I 4831.

Then I tried the same load with 85gr. HPBT Sierra Game Kings that someone gave me and the first and second group were about 1/4".

And this rifle is getting kinda tired, the throat is worn and I have to use longer bullets now.

Hip

sand pit was empty last thursday.

A fellow I know had a 243 in a 788. He loaded 105 speer semi-sptz. He thought they were the greatest deer bullet ever made. They did shoot well, 1" or so, they certainly stabilized.

The Speer 105gr. were supposed to be the answer for .244 Remington rifles with 1 in 12 twists. They were shorter than other bullets.

Hip

i also load IMR and H 4350 in my .243 win. 100 gr. hornady BTSP

I tried 43.5 of Staball=6.5 and that seems pretty good also. Had the Labradar working.
Average was 3009fps

I wouldn't bother with 105 gr RN! has nothing to offer in most cases. 5 grs of bullet and rn, JUST SAYING