Accurate Subsonic Load

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Re: Accurate Subsonic Load

Post by Guest762 » Thu Jul 16, 2015 6:15 pm

Especially not over 9.9 of 4227 @1.98 coal

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Re: Accurate Subsonic Load

Post by polizei1 » Thu Jul 16, 2015 9:25 pm

RDA wrote:
Makaio wrote:I shoot a remington 700 aac-sd 300blk bolt gun. Can anyone suggest a sub load thats accurate out of my configuration. Factory hornady 208's and umc 220's are 2-3" at best. Id love to get some sub 1" groups.
You have your work cut out for you. I can get near 1 MOA (at 100 yards) with Nosler Custom Competition / Sierra Match King in 220 grain and Hornady AMAX in 208 grain from a 9" AAC barrel.
polizei1 wrote:I'll be loading up some 240gr Leatherhead's in the next month or so when I have time and will be doing velocity/accuracy testing at 100yards.
Good luck with that, looking forward to your results, mine were not particularly good.
What kind of loads were you shooting? Right now I have mine loaded to 2.10" and I've read people going all the way down to 1.90". I'll probably test that deviation in length with 8.5gr of Lil'Gun (~1060fps) out of my 8.2" Noveske. My grouping so far was "fist size" at 50 yards, but I was shooting with a Trijicon SRS. I just got a Vortex Diamondback HP 4-16 so I'm hoping to be able to tighten them up some!

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Re: Accurate Subsonic Load

Post by RDA » Fri Jul 17, 2015 12:02 am

polizei1 wrote:
RDA wrote:
Makaio wrote:I shoot a remington 700 aac-sd 300blk bolt gun. Can anyone suggest a sub load thats accurate out of my configuration. Factory hornady 208's and umc 220's are 2-3" at best. Id love to get some sub 1" groups.
You have your work cut out for you. I can get near 1 MOA (at 100 yards) with Nosler Custom Competition / Sierra Match King in 220 grain and Hornady AMAX in 208 grain from a 9" AAC barrel.
polizei1 wrote:I'll be loading up some 240gr Leatherhead's in the next month or so when I have time and will be doing velocity/accuracy testing at 100yards.
Good luck with that, looking forward to your results, mine were not particularly good.
What kind of loads were you shooting? Right now I have mine loaded to 2.10" and I've read people going all the way down to 1.90". I'll probably test that deviation in length with 8.5gr of Lil'Gun (~1060fps) out of my 8.2" Noveske. My grouping so far was "fist size" at 50 yards, but I was shooting with a Trijicon SRS. I just got a Vortex Diamondback HP 4-16 so I'm hoping to be able to tighten them up some!
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Re: Accurate Subsonic Load

Post by Badfinger » Fri Jul 17, 2015 8:50 am

My best 300 subsonic load to date in both 16" & 9" barrels is 12.2 grs of 1680 with a 220 gr Sierra MatchKing bullets and Winchester small rifle primers! I don't have a current target but it shoots MOA at 100yds all day long

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Re: Accurate Subsonic Load

Post by polizei1 » Fri Jul 17, 2015 10:50 am

RDA I'm interested in getting out to test them now. I really want to see more data on these. I'm also surprised that you're getting the SD's you are on the 650. I've been reloading pistol for a few years now and I'm not able to get that close, I probably average ~20-30 SD. I even have the bearings and clipped spring!

I also noticed while loading the dummy loads, 2.18" would work in my Noveske. I loaded probably ~50 rounds as my initial test and got to the range and found out they wouldn't chamber, I thought that was very odd. I backed them down to 2.10" and went to the range again and out of ~50 rounds last time, 2 wouldn't chamber, so I'm thinking of dropping the OAL down even more.

What's the shortest you've gone? 2.078"?

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Re: Accurate Subsonic Load

Post by RDA » Fri Jul 17, 2015 11:14 am

polizei1 wrote:RDA I'm interested in getting out to test them now. I really want to see more data on these. I'm also surprised that you're getting the SD's you are on the 650. I've been reloading pistol for a few years now and I'm not able to get that close, I probably average ~20-30 SD. I even have the bearings and clipped spring!
I have pretty good success with my powder drops out of my 650. Ball powder meters wonderfully, extruded/stick powder can be a little more challenging. My reloading room is dry and temperature controlled which I believe helps. I have seen SDs down in the 4-5 range with N320 which is the most consistent powder I have used (and that is an extruded powder as well).
polizei1 wrote:I also noticed while loading the dummy loads, 2.18" would work in my Noveske. I loaded probably ~50 rounds as my initial test and got to the range and found out they wouldn't chamber, I thought that was very odd. I backed them down to 2.10" and went to the range again and out of ~50 rounds last time, 2 wouldn't chamber, so I'm thinking of dropping the OAL down even more.

What's the shortest you've gone? 2.078"?
I had loaded and shot some at 2.080" but found 2.085" would reliably operate in my 9" AAC barrel and 2.100" would reliably operate in my 10.5" Ballistic Advantage barrel.

Very interested in your results. 100 yards with the LH bullets has been a little challenging.

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Re: Accurate Subsonic Load

Post by Makaio » Fri Jul 17, 2015 7:16 pm

RDA, whats your oal for the 16" barrels

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Re: Accurate Subsonic Load

Post by RDA » Fri Jul 17, 2015 11:46 pm

Makaio wrote:RDA, whats your oal for the 16" barrels
I don't have a 300 Blackout 16" barreled upper built currently (although I have a 16" barrel sitting here and parts trickling in). But, the OAL is based on the chamber, not the barrel length.

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Re: Accurate Subsonic Load

Post by rjacobs » Sat Jul 18, 2015 12:01 pm

Makaio wrote:RDA, whats your oal for the 16" barrels
Some posters, yet again, have been talking about ar's in a bolt gun thread which confuses things.

Rda is right though as oal is more gun dependent than barrel length.

In ar15's the oal is usually run real short for feeding.

In a bolt gun run the oal out long. 2.260, maybe longer. My rem700 bolt will feed just fine at 2.260 and possibly longer, but i didn't check chamber depth to go longer.
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Re: Accurate Subsonic Load

Post by RDA » Sun Jul 19, 2015 12:05 pm

rjacobs wrote:
Makaio wrote:RDA, whats your oal for the 16" barrels
Some posters, yet again, have been talking about ar's in a bolt gun thread which confuses things.
Sorry about that, I thought it was an AR thread and misread the OP in my haste.

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