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Re: Subsonic for AW

Posted: Mon Jun 29, 2015 12:43 pm
by dromia
For the vast majority of shooting they are superior to jacketed, sorry if wanting to use the best puzzles you.

When it comes to subsonic loads they are especially easy to get to work as the start pressure is less than jacketed.

Re: Subsonic for AW

Posted: Mon Jun 29, 2015 1:05 pm
by DW58
It goes both ways - I have no wish to use lead bullet, simples.

Re: Subsonic for AW

Posted: Mon Jun 29, 2015 1:06 pm
by dromia
So long as the narrow view suits you then good luck to you.

Re: Subsonic for AW

Posted: Mon Jun 29, 2015 1:08 pm
by dodgyrog
DW58 wrote:It goes both ways - I have no wish to use lead bullet, simples.
Do you have any good reason for that decision?

Re: Subsonic for AW

Posted: Mon Jun 29, 2015 1:18 pm
by DW58
Why do I need to justify my decision - I wish to use jacketed bullets, I'm not going to explain why.

Re: Subsonic for AW

Posted: Mon Jun 29, 2015 2:50 pm
by ColinR
I'm with you DW58 - I only use lead bullets for low velocity cartridges in my Marlin. For anything at high velocities in target rifles I still only use FMJ. If lead is so much better than anything else, and given it is cheaper, one might question why, to the best of my knowledge, no major ammunition manufacturer offers full bore rifle ammunition loaded with lead bullets, or the military for that matter. Jacketed bullets were a major development from lead bullets 150 years or so ago, so was that a backward step?

I have now sourced some Lapua B416 200grain bullets and IMR Trail Boss, so looks all set for some fun load development.

Re: Subsonic for AW

Posted: Mon Jun 29, 2015 4:21 pm
by DOGGER2UK
Correct me if I am wrong, but ar'nt subsonics low velocity ?

I also use the lapua B416 in my AI but at 43p a bullet you can see the attraction of using lead.
Some advice. Do all your load development with the moderator OFF the rifle. Use a chrono and when you think you have a load that is subsonic, fire it at a target 5 feet from the muzzle. If you have perfectly round holes then try the moderator on the rifle.

Do a search on the Forum there has been a lot of subsonic talk in the past.

Re: Subsonic for AW

Posted: Mon Jun 29, 2015 4:28 pm
by greenshoots
Would I need to bulk up the powder as +12 grains is very little in a 7.62 case: and standard or magnum primers? regards Colin

on no account should you bulk up or use fillers with trailboss stick to published loads there is a formular given out by imr but in your case stick with imr written data

greenshoots

Re: Subsonic for AW

Posted: Mon Jun 29, 2015 4:41 pm
by greenshoots
heres a load for a 308 win with cast 150gr head and trail boss 10 grs starting load- 14grs max

http://www.imrpowder.com/PDF/Trail-Boss-data.pdf

greenshoots

Re: Subsonic for AW

Posted: Mon Jun 29, 2015 6:54 pm
by ColinR
DOGGER2UK wrote:Correct me if I am wrong, but ar'nt subsonics low velocity ?

I also use the lapua B416 in my AI but at 43p a bullet you can see the attraction of using lead.
Some advice. Do all your load development with the moderator OFF the rifle. Use a chrono and when you think you have a load that is subsonic, fire it at a target 5 feet from the muzzle. If you have perfectly round holes then try the moderator on the rifle.

Do a search on the Forum there has been a lot of subsonic talk in the past.
Yes you are spot on, Subsonics are low velocity, but equally the AI is, by my definition, a "target rifle", hence my wish to use jacketed bullets at all velocities, a personal preference I confess to. Also its about trying to replicate the Lapua subsonic with the B416 and having a great deal of faith in advice from ovenpaa as a starting point.

You seem to be telling me that the bullet can become unstable immediately after it leaves the barrel and might disrupt the baffles in a moderator. It's worth thinking about but I cannot see that happening if the MV is between 1000 - 1100 fps. If the bullet is tumbling leaving the barrel then something is clearly very wrong and I can't quite get my head around how that could happen, but I stand to be educated by those more informed.