Tac 20 barrel length and twist

[nightwalker]

What weight bullets would work best in a Tac 20, 26" pac nor, with a 1:9 twist rate, any predictions on velocity.

I have the possibility of one such rifle, trued rem 700 action, shilen trigger, boyd thumbhole stock) and wanted to know if this would be a good barrel choice OR is it a comprimise on something else?

Cheers

 

[garyw]

HI RICHARD.
a 26in bbl with 32 vmax depending on powder will get you with a good load approx 3900-4150 for top accuracy.
for 40gn bulletts berger or vmax again depending on powder you should get 3650-3950 for top accuracy.iv found n133 works best for the 32[vmax and sierras]and rel 10x for 40 berger,vmax and the sierra 39 are very accurate.
powder in the burn rate of these should work well including ramshot hodgdon-benchmark.h 4198. h335.
iv tried varget but it seems too slow as was n135.
garyw

 

[halfmile]

The 9 twist will work against you with the small bullets. Ifyou want to go fast with light bullets a slow twist will be kinder to the projectile.

You only need enough RPM to stabilize it.

HM

 

[nightwalker]

From this do I take it that I will have bother with the 32 and 40 grainers??

 

[garyw]

RICHARD.
sorry i didnt see the 1/9 twist for your barrel i presumed 1/12 which i have. for1/9 you will lean towards 50gn bulletts which will be slower.i guess velocitys around 3750-3900 depending on which powder.buts thats a guess im sure someone will post with data.
garyw

 

[eggman]

Richard,
I ran this setup on Quickload using the 50 gr. Berger bullet. QL shows that you would be looking at 3280 to 3300 fps.. Not to shabby for such a small case and efficient as well. I have had problems shooting lighter bullets such as 40 gr. bullets in a 9" twist with bigger cases like the 20 BR they just wouldn't make it to target at 100 yds.but you shouldn't have any problems at lower velocities but I'm only guessing. Looking at the QL data it looks like RamShot's TAC and H-335 would be a good powder choices. RL-15 and Varget may be a tad slow but should work as well. This would be a specialty rig for sure but sounds like it would be lots of fun.

Rodney