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Mikeinfwa
07-07-2017, 02:51 PM
Looking at the .308 FT/R 30 inch... 1 in 12 twist

According to Lutz bullet stabilization data the heavy 175, 185 and up will not stabilize with 1 in 12 twist.

I plan to shoot 1000 yards.

Savage website does not provide any information (that i could find) on what this rifle is tuned for...

is it tuned for 155's at 1000 yards?

or mid range ?

Thanks

Mike

Robinhood
07-07-2017, 10:01 PM
I have shot the 175's and the 185's with excellent results. The throat can be modified for optimal results. Stock, the Berger 155.5's are hard to beat. I believe in the long run the 185's shoot a touch better than the lighter bullets...at the expense of increased recoil. The bigger question, is the shooter good enough to tell the difference.

Price and recoil point to the 155's

Blackthorn
07-08-2017, 10:46 AM
1-12 30" barrel was built for the 155gr which complies with the Palma rules restrictions. I have gotten excellent results with Sierra 155 TMK and Varget. I push them as fast as I can to maintain good velocity at 1K. They also work great at midrange. Unfortunately the are not wind buckers so wind calls are a bit more critical.

If you want to shoot heavier bullets roll the barrel and buy a 30" in 1-11 or 1-10. That'll keep you from chasing your tail with the heavier bullets.
Accuracy seems to diminish as you get higher in bullet weights with a 1-12.



33953396This target is 46gr

penna shooter
12-08-2017, 12:52 PM
Good shooting....Well done sir

clm2112
12-09-2017, 08:11 AM
Ditto to Blackthorn's comments. It is a balancing act... how much energy is used to rotate the bullet vs. energy used to accelerate it. The lower twist rate is better for the lighter 155gr or less (more velocity, less angular momentum.) Faster twists for the heavier 168gr and up (more angular momentum to stabilize the heavier bullet at the expense of a lower muzzle velocity.) For example, in a X-Course match rifle, I use a 1-10 twist to launch 168 SMK's, trying to get the most stable flight knowing that I don't have to make it beyond 600 yards. For a 1000 yard Palma rifle, I would use a 1-14 twist to get the highest velocity out of the 155gr SMK.

Tempest
12-09-2017, 11:35 AM
I shot the 185 Juggs with a 1-12 twist for 1,000 yard FTR. Not the ideal twist but it will work. The 155's are great with that twist at 600 but they give up a lot in the wind at 1,000 compared to the 185's.