Has anyone made a Subsonic 7-08 load?

[Ricky C]

Hey,

I would like to develop a subsonic load for a bolt action 7-08 using a 175 gr bullet. I'm wondering if anyone has a load already developed that they would share. I haven't found anything published.
Thanks and Take Care

 

[Bucklowery]

The hard part is the consistent powder burn to get accuracy. 308 it can be done and similar cartridge so sure. Just start high and work down. The velocity to be subsonic comes quickly. Powder burn and neck tension to be accurate is another thing. Also a bullet to expand at lower velocity is another issue if needed. I have not seen any .284 bullets for expanding at low velocity

Thanks

Buck

 

[CMP70306]

I would try trailboss in the 9 to 12 grain range depending on your case fill and other factors such as bullet shape and twist rate.

I just did subsonic load work ups in a 30-06 and 12.5gr got me 1050 fps with a 208gr bullet in a 20" 8 twist barrel. With a 178gr bullet I got 1133 fps with the same powder charge.

In your case check to make sure that doesn't result in a compressed load then work down to get subsonic. You won't get any expansion at that velocity and I don't know of any subsonic expanding bullets for the 7mm like there is for the .30 cal.

 

[Bucklowery]

Trailboss if you can find it. It is almost non existent. Vit tin star was the next one and I heard they are discontinuing it too.

Thanks

Buck

 

[Ricky C]

Hey,
Thanks, I was thinking Trail boss was probably going to be the one to try. There's a small gun store close by and I found two lbs of RL26 in there yesterday, maybe they'll have some Trail boss!
Take Care

 

[del2les]

As already stated, Trail Boss is a great one, but I have made various caliber reduced and sub loads using Red Dot. In the 7-08, I would start with around 12 grains of Trail Boss and work DOWN from there, so as to avoid a stuck bullet. Lyman Cast Bullet Manual can be used as a guide on various pistol/shotgun powders for this application, and many times, I prefer to use cast bullets for this application. They have a lower friction ratio than jacketed and are less likely to lodge in the bore at lower speeds.

 

[CMP70306]

As already stated, Trail Boss is a great one, but I have made various caliber reduced and sub loads using Red Dot. In the 7-08, I would start with around 12 grains of Trail Boss and work DOWN from there, so as to avoid a stuck bullet. Lyman Cast Bullet Manual can be used as a guide on various pistol/shotgun powders for this application, and many times, I prefer to use cast bullets for this application. They have a lower friction ratio than jacketed and are less likely to lodge in the bore at lower speeds.

Additionally to piggyback on that solid copper projectiles go the opposite way, and have more friction for example with 12.5gr Trailboss I got 1050fps with 208gr BTHP, 1133fps with the 178gr ELD-X and 868fps with a 188gr Subsonic Copper bullet.

Also I did get a copper bullet stuck at the end of my revolver barrel once, the load that would push a 250gr jacketed bullet at 900 fps didn't leave the barrel when switching to an all copper bullet. As such always start high and work down.

 

[Reelamin]

Trail Boss if you can find it. In my Subsonic 6.5 CM 140gr, I'm right around 10gr for nothing over 1050fps.