300 Blackout Journey Page 7 – “Hammer Of Thor”

Reloading is such a rewarding experience for me, the thrill of the chase in trying to produce the most accurate ammunition possible and the fun of being on the range testing makes for a great day. I now have been reloading 300 Blackout for some time and have documented my loads and experiences in this journal.

Wanting to try some of the heavier subsonic bullets like the 220gr Sierra Pro Hunter, Missouri Bullet Company 245gr Lead Bullet and the 203gr Palmetto Lead Coated bullet all in an effort to drive down cost I ordered small amount of each. Immediately I noticed the lead bullets would shave no matter how straight you had them aligned. Leaning on my experience of having loaded tens of thousands of lead 45ACP and 44Magnum rounds I knew right away I needed to flair the neck of the?300 blackout case. I purchased a universal Lee Expander rifle die, I have a lot of Lee dies and they have served me very well. This particular die just wasn’t what I was looking for it only really flared the mouth.?To keep the lead bullets from shaving I felt?the expansion of the mouth of the case was extreme with the Lee Die, though I am sure it would work great on other calibers. A friend of mine who has a lot of reloading experience about 25years of it, 6 years more time behind a press than I do recommended the Lyman M Die.

This would be exactly what I was looking for, the Lyman M Dies expands the case and the neck of the case in two stages. Please be sure to pay attention to item number on the box in the photo it is important that you get exactly this model. There is another model which won’t work as well due to overall length. With the use of this die all of my troubles would go away. A great side effect I have noticed is that my rounds all seem to be more accurate as well. So I have changed my reloading routine to include expanding the neck of all my rounds including jacketed.

Being very interested in the Sierra Pro Hunter or as I would name it “The Hammer of Thor” I would load up some of these rounds with my favorite 300Blackout Subsonic powder A1680. Rounds are checked with the Sheridan Slotted Gauge to ensure fit in the rifles I test with. This powder produces great subsonic groups with 220gr Sierra Match King this load would not prove to be as accurate.

Rifle Barrel Length Gas Tube Length Ammunition – Powder-Manual COAL Bullet Weight/Bullet Type Velocity FPS Average Velocity FPS ES SD Group Size Weather Conditions Bolt Lock Back
RARR 300BlackOut 16′ 1/7 Twist N/A Reload 11.3gr A1680 2.065 SierraProHunter 220gr Hi 1112 1085 55 24 1.391 79 Degrees N/A
Low 1057
1065
1089
1105
Sun Devil Lower CMMG Barrel 300BlackOut 16′ 1/7 Twist N/A Reload 11.3gr A1680 2.065 SierraProHunter 220gr 1090 1098 35 16 1.424 79 Degrees Yes
1112
Low 1084
1085
Hi 1119

Though not as accurate as I would have liked I decided to press this round into my first 200 yard test with my Ruger American Ranch Rifle.

My hope is to develop an accurate 200 yard round utilizes the Sierra Pro Hunter “Hammer of Thor” round. I know many of you may wonder why try this with a subsonic round, like I said it is about the chase and excitement of accomplishment as a reloader, nothing more. With two targets hung in a vertical fashion I would fire two 5 shot groups, 10 shots were on paper with two distinctive groups but not as tight as I had hoped.

DSC01383With a little more development of the 50 Yard Lilgun load listed below I may give the 200 Yard test another try.

 

Rifle Barrel Length Gas Tube Length Ammunition – Powder-Manual COAL Bullet Weight/Bullet Type Velocity FPS Average Velocity FPS ES SD Group Size Weather Conditions Bolt Lock Back
RARR 300BlackOut 16′ 1/7 Twist N/A Reload 8.6gr LilGun 2.065 SierraProHunter 220gr 1097 1091 22 9 0.558 79 Degrees N/A
1086
1085
Low 1083
Hi 1105
Sun Devil Lower CMMG Barrel 300BlackOut 16′ 1/7 Twist N/A Reload 8.6gr LilGun 2.065 SierraProHunter 220gr Hi 1098 1085 30 11 1.074 79 Degrees Yes
1083
1083
1094
Low 1068

The other 50 yard loads developed for this trip I am not so sure is worthy of the 200 yard test. What would you consider to be good accuracy for 300 Blackout subsonic at 200 Yards?

Leave a comment.

 

Rifle Barrel Length Gas Tube Length Ammunition – Powder-Manual COAL Bullet Weight/Bullet Type Velocity FPS Average Velocity FPS ES SD Group Size Weather Conditions Bolt Lock Back
RARR 300BlackOut 16′ 1/7 Twist N/A Reload 8.3grAA#9 2.065 SierraProHunter 220gr 1017 1024 33 13 1.153 79 Degrees N/A
Low 1007
1020
Hi 1040
1036
Sun Devil Lower CMMG Barrel 300BlackOut 16′ 1/7 Twist N/A Reload 8.3grAA#9 2.065 SierraProHunter 220gr Hi 1058 1012 128 50 1.462 79 Degrees No
1049
1017
1008
Low 930
RARR 300BlackOut 16′ 1/7 Twist N/A Reload 10.3grA5744 2.065 SierraProHunter 220gr 1086 1089 92 36 1.149 79 Degrees N/A
` Hi 1153
1069
Low 1061
1079
Sun Devil Lower CMMG Barrel 300BlackOut 16′ 1/7 Twist N/A Reload 10.3grA5744 2.065 SierraProHunter 220gr 1171 1153 69 27 2.347 79 Degrees Yes
Hi 1184
Low 1115
1160
1135

Stay safe and?have fun on your next dayattherange.

Continued on 300Blackout Journey Page8