180gr rainier plated hollow point subsonic loads

[Bob the nailer]

Picked up some CFE BLK for the 180 Rainier's, starting loads will be 9.5, 9.8, 10 and 10.3grains to check for velocity. Picked 2.090" as a starting c.o.l. and seem to feed good from the Pmag. I must say as a first time sub load work up there is a LOT of empty space in that case is filling remainder of space with puff lon a bad idea?


16" pistol gassed, 1-8 twist

[Bob the nailer]

Range time with first sub loads.

CFE BLK
Rainier 180 wedge flat point
10.3 grains 955fps, 931fps


10 grains 873fps, 906fps


9.8 grains 893fps, 958fps


9.5 grains 885fps, 822fps


The 9.5 grain load would not hold bolt open on last round all others did. Only shot at 50 yards and wasn't concerned about accuracy just velocity. Are the big velocity spreads in a given charge due to powder position in the case? At 662' elevation the slow numbers don't surprise me I'll try to hit 1050fps on next trip out.

16" pistol gassed, 1-8 twist, 62 degrees F, chrony at 10' from muzzle.

[gavinjones2002]

Range time with first sub loads.

CFE BLK
Rainier 180 wedge flat point
10.3 grains 955fps, 931fps


10 grains 873fps, 906fps


9.8 grains 893fps, 958fps


9.5 grains 885fps, 822fps


The 9.5 grain load would not hold bolt open on last round all others did. Only shot at 50 yards and wasn't concerned about accuracy just velocity. Are the big velocity spreads in a given charge due to powder position in the case? At 662' elevation the slow numbers don't surprise me I'll try to hit 1050fps on next trip out.

16" pistol gassed, 1-8 twist, 62 degrees F, chrony at 10' from muzzle.

I haven't tried CFE BLK with this bullet but based on dellet's extensive work with that powder it definitely performs best when compressed, empty case volume can always contribute to increased SD/ES. Since you're running a pistol gas AR I would recommend IMR4198 as it has a pretty high VMD to fill more of the case. TKO and I have both found some pretty reliable loads with that powder. Below are some of my 4198 loads with this bullet and a 10.5" pistol AR:

Primer COAL FPS SD ES Load (gr)
CCI 400 2.12 942 45 135 10.5
CCI 400 2.12 1018 55 175 11
CCI 450 2.12 1032 44 130 11
CCI 400 2.05 1033 29 74 11
CCI 400 2.12 1028 27 57 11.5
CCI 400 2.135 1013 15 56 12

Hope this helps,
Take care

[PNW17]

I have ran the flat points with zero problems using Lancer's

Almost every round jams into the feed ramps even with the lancers. I just ground down the feed ramps with a stone in my Drexel and that seems to help but we'll see. I will polish them with lapping compound when I have a chance as well.

Ran these again today after working on the feed ramps. They cycled slightly better but not by much. The rounds hit the feed ramp and get hung up. Then, because I can't put a firm crimp on them, the bullet jambs back into the case and gets really short. I'm close to being done with these.

Finally had great results yesterday. Used the pmag blk magazines which have solved all my feeding problems. 11grs of N120 @2.1" oal produced 950fps average out of the 8" bbl and liberty mystic x. Every round cycled perfect with full function and last bho. The N120 is so much cleaner than 1680, I don't have to clean it after every use now. No more large un burnt grains everywhere in the action.

[Dr.Phil]

Finally had great results yesterday. Used the pmag blk magazines which have solved all my feeding problems. 11grs of N120 @2.1" oal produced 950fps average out of the 8" bbl and liberty mystic x. Every round cycled perfect with full function and last bho. The N120 is so much cleaner than 1680, I don't have to clean it after every use now. No more large un burnt grains everywhere in the action.

Shush........
Don't tell too many people.
N120 is hands down, the best powder for subsonic 300 BLK loads.
Some other super fast pistol powders may be more quiet, but nothing is cleaner, more consistent, or more accurate.

Congrats!!!

[Bob the nailer]

Firearm being used: AR15, CBC upper socom barrel taper
Barrel Length:16"
Gas length(if applicable):pistol
Powder:IMR4227
Grains:10.2
OAL: 2.090"
Velocity(if available):1000fps
(anything else you feel is relevant to the load)
Use a Lee collet neck die after a F.L. resize, light to medium crimp, powder position is not a problem. Check you seating die stem to verify contact with bullet ogive area, bullets side tapper runout is not consistent enough.

Sub-Moa at 100 yards in my AR.

[TKO]

Regarding Trail Boss:

I have been playing with it in a RARR chambered in 300 AAC Blackout with Rainier Ballistics 180 grain plated HP's for a cheap and quiet "Bunny Fart" load. I used a cutaway case to determine where my bullet base was situated and loaded enough powder to reach the bullet base without compression of the powder. 5.0 grains.

Average velocity 10 ft from muzzle 811 fps
ES: 67 fps
SD: 15 fps

Very quiet:

https://photos.google.com/photo/AF1QipO ... 5jfByhSPXM

Actually, way more (stupid) quiet outside of the garage, but I don't have a video of that.

Decided to try a 0.5 grain bump to 5.5 grains with attendant mild compression and velocity average climbed to 865 fps but both ES and SD more than doubled, so things were getting erratic. I highly recommend that you do NOT compress this powder.

I have plenty of throat and magazine room to seat the bullets further out for more effective case capacity, but I am happy with things the way they are for now.

[dellet]

Regarding Trail Boss:

I have been playing with it in a RARR chambered in 300 AAC Blackout with Rainier Ballistics 180 grain plated HP's for a cheap and quiet "Bunny Fart" load. I used a cutaway case to determine where my bullet base was situated and loaded enough powder to reach the bullet base without compression of the powder. 5.0 grains.

Average velocity 10 ft from muzzle 811 fps
ES: 67 fps
SD: 15 fps

Very quiet:

https://photos.google.com/photo/AF1QipO ... 5jfByhSPXM

Actually, way more (stupid) quiet outside of the garage, but I don't have a video of that.

Decided to try a 0.5 grain bump to 5.5 grains with attendant mild compression and velocity average climbed to 865 fps but both ES and SD more than doubled, so things were getting erratic. I highly recommend that you do NOT compress this powder.

I have plenty of throat and magazine room to seat the bullets further out for more effective case capacity, but I am happy with things the way they are for now.

I think that's what most people find with compression.
For what it's worth Vihtavuori Tin Star has the same qualities, but about 60% of the bulk. It works real well for bullets up to 1.5" long. Price is not that much more than Trail Boss when you consider pound for pound.

[TKO]

Regarding Trail Boss:

I have been playing with it in a RARR chambered in 300 AAC Blackout with Rainier Ballistics 180 grain plated HP's for a cheap and quiet "Bunny Fart" load. I used a cutaway case to determine where my bullet base was situated and loaded enough powder to reach the bullet base without compression of the powder. 5.0 grains.

Average velocity 10 ft from muzzle 811 fps
ES: 67 fps
SD: 15 fps

Very quiet:

https://photos.google.com/photo/AF1QipO ... 5jfByhSPXM

Actually, way more (stupid) quiet outside of the garage, but I don't have a video of that.

Decided to try a 0.5 grain bump to 5.5 grains with attendant mild compression and velocity average climbed to 865 fps but both ES and SD more than doubled, so things were getting erratic. I highly recommend that you do NOT compress this powder.

I have plenty of throat and magazine room to seat the bullets further out for more effective case capacity, but I am happy with things the way they are for now.

I think that's what most people find with compression.
For what it's worth Vihtavuori Tin Star has the same qualities, but about 60% of the bulk. It works real well for bullets up to 1.5" long. Price is not that much more than Trail Boss when you consider pound for pound.

It's funny you mention "pound for pound" . . . I thought I was getting a smoking deal on my first jug of Trail Boss until I realized it was the same size jug as the other offerings but only contained 9 ounces of powder.

I see where Tin Star is listed as 420 g/l so it is the fluffiest stuff in their line of powders.

How well does it meter?

[dellet]

Regarding Trail Boss:

I have been playing with it in a RARR chambered in 300 AAC Blackout with Rainier Ballistics 180 grain plated HP's for a cheap and quiet "Bunny Fart" load. I used a cutaway case to determine where my bullet base was situated and loaded enough powder to reach the bullet base without compression of the powder. 5.0 grains.

Average velocity 10 ft from muzzle 811 fps
ES: 67 fps
SD: 15 fps

Very quiet:

https://photos.google.com/photo/AF1QipO ... 5jfByhSPXM

Actually, way more (stupid) quiet outside of the garage, but I don't have a video of that.

Decided to try a 0.5 grain bump to 5.5 grains with attendant mild compression and velocity average climbed to 865 fps but both ES and SD more than doubled, so things were getting erratic. I highly recommend that you do NOT compress this powder.

I have plenty of throat and magazine room to seat the bullets further out for more effective case capacity, but I am happy with things the way they are for now.

I think that's what most people find with compression.
For what it's worth Vihtavuori Tin Star has the same qualities, but about 60% of the bulk. It works real well for bullets up to 1.5" long. Price is not that much more than Trail Boss when you consider pound for pound.

It's funny you mention "pound for pound" . . . I thought I was getting a smoking deal on my first jug of Trail Boss until I realized it was the same size jug as the other offerings but only contained 9 ounces of powder.

I see where Tin Star is listed as 420 g/l so it is the fluffiest stuff in their line of powders.

How well does it meter?

It probably has the most bulk. It meters reasonably well, it's basically a short stick powder, but actually it's a tube.

For an idea of volume my brass holds 24.7 grains of 296 to the top of the neck. 7.0 of Trail Boss, 10.0 of TinStar.

The good and bad thing is in a bolt gun or single shot you can load a long heavy bullet long enough with enough powder to hit 70,000 psi.

For an idea of a starting load, a favorite is
208 Amax
2.200"
7.0 grns Tinstar
1020 avg
16" Handi.

I think it works reasonably well with lower density charges so with something like the Rainier 6.5 grains might be a good place to start. I can add that to the weekend list, could be fun.