Trail Boss in 7.62 x 54R with regular projectiles

[Vince24]

Hi guys

I got a bottle of trail boss cheap in a private deal.

I have got a beautiful Mosin M91/30 that is incredibly gorgeous but shoots way too high (e.g. 50cm too high at 100m) and tends to overheat quickly too.

I am doing something stupid by attempting a load development with trail boss and a regular Speer 180 grains SP 311 projectile?

Will this drop significantly the point of impact?

Never used Trail Boss before.

[Fester]

My 30-30 shoots a good 8-10" lower with pop loads at 50yds.
Only testing will tell much it drops.

[bladeracer]

Hi guys

I got a bottle of trail boss cheap in a private deal.

I have got a beautiful Mosin M91/30 that is incredibly gorgeous but shoots way too high (e.g. 50cm too high at 100m) and tends to overheat quickly too.

I am doing something stupid by attempting a load development with trail boss and a regular Speer 180 grains SP 311 projectile?

Will this drop significantly the point of impact?

Never used Trail Boss before.

15gn of Trailboss with Bertram's 174gn .311" SP is a very pleasant load, or 10gn if you want to go subsonic.
Yes, it will significantly lower PoI. I haven't shot the subsonic load since 2022. My regular loads shoot around 150mm low at 100m. My logbook says the subs were 120mm low at 50m last time I tried them.

[Vince24]

Thanks!

So really no issue is shooting conventional jacketed bullets with Trail Boss, right?

I like that their guidance says that the maximum load is to fill the case till the base of the bullet, but that's not easy to precisely estimate! Hopefully there is a big safety margin in their guidance.

[bladeracer]

Thanks!

So really no issue is shooting conventional jacketed bullets with Trail Boss, right?

I like that their guidance says that the maximum load is to fill the case till the base of the bullet, but that's not easy to precisely estimate! Hopefully there is a big safety margin in their guidance.

None at all, I use it in all my milsurps and hunting rifles, from the .204 upward.

It doesn't need to be precise and I've seen no issues from compressing TB, even in 12ga. shells. You can leave air-space in there as well, it's not like blackpowder. I run 2.0gn in .38 Special and there is still a huge amount of empty space under the bullet. If you run very low charges and do see inconsistency try some light filler material to keep the powder on top of the primer. In Cowboy, the pistols are holstered so the powder is resting on the base of the bullet, as far from the primer as possible. I've heard reports of it causing squibs but I haven't seen it myself. I certainly see a lot of squibs in Cowboy but none that can definitively be attributed to this situation, they usually result from no powder at all, with the bullet barely making it into the rifling.

[No1Mk3]

Personally I would follow ADI's warning not to compress Trailboss due to erratic preesure spikes that were measured during development. As to the Mosin shooting high this is normal for them, with a zero set at 300 Arshin (213 meters) and the later /30 not altered from this they almost all shoot high at 100m unless someone has previously altered them. For all of mine I load a 2600 fps cartridge, usually Hornady 303 174g, (.3015 projectile) and change the front sight post in the carbines to get a 100m zero.

[Vince24]

yeah but mine is shooting WAY too high.
With the rear sight setting at 100m, I took 3 shots at the military target placed at 300 yards. It was still 50cm too high
Look at the pic below. The group was good though, for 300 yards!
Given it's the same discrepancy at 100m or at 300 yards, I wonder the barrel might be bent...

Thanks for the advice, I will see what Trail Boss does with this Mosin.

300 yards 3 shots.jpg (265.65 KiB) Viewed 6591 times

IMG_1826.jpg (587.45 KiB) Viewed 6591 times

[Vince24]

just one more question though, how do you handle trail boss?

I have measured I would have up to 18 grains of TB in my 7.62 x 54R with a 180 gr bullet seated at 2.950.

But when I try to get 70% of that (12.6 grains) through my Lee Perfect Powder, it's quite a nightmare?! the trail boss just dies not like going down that thing!
It feels like more efficient to just use a small container and finalise with a trickler.

Cheers
Vincent

[bladeracer]

just one more question though, how do you handle trail boss?

I have measured I would have up to 18 grains of TB in my 7.62 x 54R with a 180 gr bullet seated at 2.950.

But when I try to get 70% of that (12.6 grains) through my Lee Perfect Powder, it's quite a nightmare?! the trail boss just dies not like going down that thing!
It feels like more efficient to just use a small container and finalise with a trickler.

Cheers
Vincent

I use it in the Lee Perfect Powder Thrower with no issues. I have also done it just with a scoop onto the pan on the scale, I don't bother trickling.
Keep the reservoir full, give the lever a good tap at the top of the stroke, and it should flow fine. I throw tiny loads with it.

[Fester]

Best just tipped in with a Lee measure spoon and trickle up.
The reason you don't compress TB is that breaking rings changes its burn rate dramatically.

I have done a reduced .223 load and it shot better than my .22 mag at 100m, and quiet.

The 30-30 shot well at 50yd, but was starting to keyhole at 100.
I went back to higher loads of 2208 to shoot the powder coated 165 projies and made some good splashes on the 300m mound, surprizing both me and the RO. I just aimed at the top of the low mound and was hitting in the middle.

[Vince24]

Thanks everyone.

One more, is there a recommendation as to the type of primers to be used with trail boss?
E.g. Large pistol, standard rifle, magnum etc. I have everything.

[bladeracer]

Thanks everyone.

One more, is there a recommendation as to the type of primers to be used with trail boss?
E.g. Large pistol, standard rifle, magnum etc. I have everything.

I prefer magnum rifle primers anyway, it's just easier than using two different primers, but I don't think it's required.

[Vince24]

Thanks guys I have shot my first reduced loads this we.

14.5 grains, just to see the POI change.

And it was quite dramatic, I had to set the sights on 700m to be in the target at 100m )
I got more than i bargained for on that matter.

The reduction in recoil is also quite dramatic compared to the previous 45 grains of 2208!
It felt like shooting a 22 Magnum in a light lever action.

Cheers
Vincent

[bladeracer]

Thanks guys I have shot my first reduced loads this we.

14.5 grains, just to see the POI change.

And it was quite dramatic, I had to set the sights on 700m to be in the target at 100m )
I got more than i bargained for on that matter.

The reduction in recoil is also quite dramatic compared to the previous 45 grains of 2208!
It felt like shooting a 22 Magnum in a light lever action.

Cheers
Vincent

Yep, you can shoot TB loads all day long and not get tired of it