RevolverRob's Loading Journal (mostly .38 Spl and .45 ACP)

[RevolverRob]

Little behind in updating on my quest to load .300BLK.

Finally got in the last of my back orders today - to load .300. I'll be doing two bullets at two different charge weights each, for my initial batch of things here.

Brass: Lake City Mil-Spec 5.56; 2006-2014 vintage; cut with tubing cutters; formed in Lee Dies
Primers: Federal Match Small Rifle
Powder: Shooter's World SBR-SOCOM
Bullets: 110-grain Barnes Tac-TX; 125-grain Speer TNT

Load #1: 125 TNT - 16g - COAL 2.12"/53.9mm

Load #2: 125 TNT - 18g - COAL 2.12"/53.9mm

Load #3: 110 grain Barnes - 17g - COAL 2.2"/56mm

Load #4: 110 Barnes - 19g - 2.2"/56mm

All four loads should come in well under max pressure and leave me room for a larger charge (~21-22g max).

[RevolverRob]

Was adjusting the powder throw to see how this SOCOM meters. It meters really well. Took me a minute to dial things in, but the Lyman Brass Smith get’s me about .1g increments with SOCOM. By contrast VV N330 I can usually only reliably get .2 in the same throw.

And in case anyone was wondering...it’s impossible to double charge a .300BO using this powder. The minimum load listed is 14g and max is 21g. Below is 21g in a case trimmed to 1.358”. No wonder Shooter’s World list 21g loads with OALs near max (2.2-2.25”). I would bet I could only get down to 2.1” if I stood on the handle when seating and compressed the living shit out of the load.

I’m only going to spin up about 20-40 of each of the TNT loads and 10 or so of the Barnes (since I only have 50 of the barnes bullets on hand right now). Once I dial in the loads, I’ll crank out a bunch of them and then move on to playing with subsonics.

Liking this powder so far - but obviously the most important aspects are yet to come in terms of performance.

[RevolverRob]

Finally got everything in to load ammo and loaded up 80 rounds tonight. I ended up doing 5 loads, 3xTNT, 2xBarnes - 20 rounds of each of the TNT loads and 10 of each of the Barnes.

1) 125-grain TNT, 16g SBR-SOCOM, 2.12" ~54mm OAL, Fed Match Small Rifle Primer (GM205M)
2) 125-grain TNT, 18g SBR-SOCOM, 2.12" ~54mm OAL, Fed Match Small Rifle Primer (GM205M)
3) 125-grain TNT, 20g SBR-SOCOM, 2.16" ~55mm OAL, Fed Match Small Rifle Primer (GM205M)
4) 110-grain Barnes Tac-X (not Tac-TX), 17g SBR-SOCOM, 2.2" ~56mm OAL, Fed Match Small Rifle Primer (GM205M)
5) 110-grain Barnes Tac-X, 20g SBR-SOCOM, 2.2" ~56MM OAL, Fed Match Small Rifle Primer (GM205M)

I adjusted the length on the TNT over 20g of SBR a little farther out, because I want to observe for any signs of over-pressure in that length range and powder charge. I don't think I'm going to see any, because I'm still below the max powder load listed in the Shooter's World manual (21g) and longer than the OAL on the nearest to max pressure load they list (21g under a 135-grain hornady FTX at 2.12" OAL, pressure is listed at around 54k PSI).

General thoughts on loading .300BO so far...

I know, in theory, that ~2.245" or ~57mm is the maximum OAL for .300BO. I tried loading a few Barnes 110s initially to that length (because that is the length Barnes lists in their loading data), but I did NOT like the lack tension on the bullet, bare handed, I managed to pull a bullet from the case, dialing it a mm shorter really improved the tension, it may have even made the taper crimp I threw on each round unnecessary (in fact it didn't 'feel' like I got much of a crimp through the handle of the press). If I ran my brass towards the longer trim length (1.368" instead of the 1.358" I trimmed to), I think I would have found the maximum OAL much more amenable. I'll bear this in mind if I feel I want to load that length in the future.

That said, loading to 2.2"/56mm over even 20g of SBR-SOCOM was no issue. I experienced no resistance in seating the bullet and I can shake the cartridge and hear powder moving, suggesting the load is not compressed. I think I could cram as much as 21.5g at 2.2" COAL, but it would be a compressed load. The 21g listed as max in Shooter's World Manual is likely accurate for a 2.2" COAL. You MIGHT cram 22g in at the 2.245" max length, if you compressed the load down and ran your brass longer, seems like that would probably be a bolt-action or single-shot load.

This SBR-SOCOM powder really does meter super well. I am +/- 0.1 grains. I weighed out each charge in the powder throw for the load I was loading +5 grains (example 20 rounds at 20g is 400g of powder, so I put 405g in the hopper). And then after throwing all 20 charges, I would dump the remaining powder from the hopper into my scale and weigh it. Each time, I used <2 grains of additional powder, in 4 of 5 cases, <1.2 extra grains. I probably didn't even "use" all of that in my cartridges, some portion of it was lost in adjusting my powder throw and some of it was likely still stuck in the powder throw. I'm very pleased with the consistency.

If I can find a pistol powder that meters this well, I'll be really happy. Not that I'm unhappy with how N330 or 3N38 meter, they just don't meter as smooth as this stuff.

[willie]

Any ball powder will meter well. You can use Win 231 to load .38 Spl, .45 Auto,, and 9mm. Alliant Bullseye meters well and applies nicely to three cartridges mentioned.

[RevolverRob]

I do not have a reloading problem...Why do you ask?