Bullet Weight for Pacnor18" 1-8 Twist Bolt Action

[milehipo]

Just looking for suggestions for bullet weight and SUBSONIC load data for a Bolt Action Rifle with a Pacnor 18" 1-8 twist barrel, of which was built on a CZ 527 platform. I have AA #9, AA 1680, and Hodgen H110 powders.
What powder and load has brought you the best accuracy?
Thank-You

[Hoser]

210 Bergers and 220 Sierra Matchkings.

[coldbeerchief]

240 SMK's on 8.4 gr of Lil Gun produce .3 MOA groups out to 220 yards in my 1:8 barrel

[jimpa]

Have a 16" 1-6.5" Pacnor, on same action. Using 220 and 240 SMKs 4227 works good using 9.5 of 296 right now,,, experamint 1/10 gr make a big difference. seating the bullets deep to keep case volume denisty up makes big difference

[rsilvers]

240 SMK's on 8.4 gr of Lil Gun produce .3 MOA groups out to 220 yards in my 1:8 barrel

You would need a 3 fps standard deviation (9 fps extreme spread) - and no one can do that with subsonic rounds.

[Titleiiredneck]

You would need a 3 fps standard deviation (9 fps extreme spread) - and no one can do that with subsonic rounds.

I can see its possible with the right conditions, I have shot quite a few groups like this with a 1-10 twist sub 308 rounds with a 190 gr smk and 220 gr smk 300 whisper loads at around 150 yds. Probally not possible with a ar platform but I am sure it can be done with a bolt or single shot setup.

titleiiredneck

[milehipo]

With a proper load developed and using a suppressor would this be a accurate and effective hunting rifle out to 150 yards for mountain lion?

[Hoser]

With a proper load developed and using a suppressor would this be a accurate and effective hunting rifle out to 150 yards for mountain lion?

If it can trade places on the food chain with you, over gun it.

[gdragon]

If it can trade places on the food chain with you, over gun it.

^^ Like ^^^^^^^^^^^

[LouBoyd]

There are other factors besides twist rate which determine what bullets you can (or should) use. What is your magazine length? 2.28" like an AR-15 or 2.8" like a typical short action bolt rifle? Can you even shoot the bullet you choose in your rifle? I'm thinking of the 220 grain LRB solid which is way to long to shoot from an AR-15 magazine.

Then there is the elevation where you shoot. You may not be able to stabilize some VLD bullets in cold weather or at low elevation. It's air density with matters. Air density can be calculated or measured directly. Obviously heavy subsonic bullets carry the most energy at the muzzle. Low drag bullets retain their energy best with distance. Low drag bullets also have the least wind deflection. You've got to hit your target in or very near a vital organ to get clean quick kills, but the bullet needs to transfer it's energy to the vital organs to be most effective not just pass though the animal.

Drop and vertical dispersion increase with the square of the time of flight for all bullets. That usually places the upper limit of the practical range of subsonic which are traveling 2 to 3 times slower than conventional hunting bullets. They will also have 4 to 9 times less energy than the same bullets fired at the velocity of typical supersonic hunting rifles. Subsonics certainly can kill, but they require considerably more skill to achieve effective shot placement.
So what's the best bullet for >your< situation? I can't tell you. The above is just some things to think about. Whatever you choose practice with it so you know what kind of accuracy you can achieve at various distances.

[LouBoyd]

There are other factors besides twist rate which determine what bullets you can (or should) use. What is your magazine length? 2.28" like an AR-15 or 2.8" like a typical short action bolt rifle? Can you even shoot the bullet you choose in your rifle? I'm thinking of the 220 grain LRB solid which is way to long to shoot from an AR-15 magazine.

Then there is the elevation where you shoot. You may not be able to stabilize some VLD bullets in cold weather or at low elevation. It's air density with matters. Air density can be calculated or measured directly. Obviously heavy subsonic bullets carry the most energy at the muzzle. Low drag bullets retain their energy best with distance. Low drag bullets also have the least wind deflection. You've got to hit your target in or very near a vital organ to get clean quick kills, but the bullet needs to transfer it's energy to the vital organs to be most effective not just pass though the animal.

Drop and vertical dispersion increase with the square of the time of flight for all bullets. That usually places the upper limit of the practical range of subsonic which are traveling 2 to 3 times slower than conventional hunting bullets. They will also have 4 to 9 times less energy than the same bullets fired at the velocity of typical supersonic hunting rifles. Subsonics certainly can kill, but they require considerably more skill to achieve effective shot placement.
So what's the best bullet for >your< situation? I can't tell you. The above is just some things to think about. Whatever you choose, practice with it so you can know what kind of accuracy you can achieve at various distances, partiularly in the presence of wind.