300BLK Build Begins - And Ends
- Thread starter BillD
- Start date
Well, I've been collecting brass for a while, and picked up some used die sets at local gun shows in addition to ordering a 300BLK die set last time I was at the range but still didn't have a reloading kit. Stumbled across this in the Cabela's bargain cave today though:
Guess I'll be going down that rabbit hole soon.
Guess I'll be going down that rabbit hole soon.
Well, I've been collecting brass for a while, and picked up some used die sets at local gun shows in addition to ordering a 300BLK die set last time I was at the range but still didn't have a reloading kit. Stumbled across this in the Cabela's bargain cave today though:
Guess I'll be going down that rabbit hole soon.
Careful, it's deep and dark and no way back out LOL!
So I hear, lol.
I like shooting .45. I've got a .308 bolt gun, a 5.56 AR and now .300blk. I'm also apparently the only person at my range that bothers to pick up their spent brass. I figure even if I'm just making "mass production" type loads it'll be worthwhile. I'm also seriously considering building an upper in .277 wolverine.
Two of my 300BLK rifles will shoot 155gr A-MAX over A1680 and Lil'Gun into sub moa groups, 155 is a little light for a 10 twist 308 but it is a good projectile you should be able to get good accuracy from in both.
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A few things that'll make life easier: tumbler for cleaning cases; calipers to measure case length, OAL, etc.; bullet puller hammer; ammo boxes; good workspace with lots of lighting! I'm sure there's a bunch of stuff I'm forgetting that I won't remember til I go to use it again lol.
Depending on the dies you ordered you may or may not need a shell holder. Order one for 223 anyway, it's nice having one or two extra if your case trimmer uses one or your hand priming tool uses one.
I don't use the press to prime my brass, I prefer to use the RCBS hand priming tool for all my cartridges. This is where a spare shell holder is nice as I can leave it ready to use whenever I'm working on 300BLK or 223.
Since you're going to be reloading for 300BLK you may want to visit your nearest Princess Auto or KMS tools and find yourself a little 6 inch metal chop saw. 223 brass is everywhere and way easier to find new than 300BLK brass. I cull all of my Remington brand brass from the rest and use it exclusively for 300BLK, so far it has converted easily and functioned perfectly for all 700 pieces I've made. I noticed the other day that I have 300 pieces of Rem 223 ready to convert so it may be time to do another batch.
Have a friend who is experienced in reloading come over and help you through the first 100 rounds you build.
Take your time and be as consistent as possible. Making mistakes can be dangerous and expensive.
Look into each case and make sure there is powder before seating a bullet.
If you're using a digital scale keep your cell phone and fluorescent lights away from it.
Normally I would say you need at least two reloading books but there isn't a lot of published data for 300BLK so the internet and other peoples loads will have to be taken into consideration. Every year there is more and more data published though so I would find a new 10th edition Hornady manual since they have quite a few loads and most people want to use cheaper projectiles in this cartridge.
Also remember that not all published loads were made for a semi auto so not all will cycle your action. So far H110 has performed well for me for supersonic loads with projectiles up to around 150gr (I don't use it above 130gr), Lil'Gun is kinda my mid weight for 130-168gr supersonic loads, A1680 is my powder for 208gr subsonics that also works well for my 155gr supersonic loads. IMR4227 is also supposed to work well but I haven't done much testing with it yet.
Just remember that this cartridge is not a miniature 308 so you can not push your velocities anywhere near those levels. It is however capable of very good accuracy and I've seen three out of four of my 300BLK rifles print sub moa 100yd groups, the fourth rifle probably would have printed better groups but I didn't spend any time on load development before selling the upper I put together.
Good luck
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Big thank you to both cr5 and Bill for the insight. A tumbler of sonic cleaner is definitely on the "to do" list. Would you fine gentleman mind schooling me on case trimmers? It seems like it's the only thing that wasn't included with my kit.
I used a Lyman hand lathe style trimmer for a few years and I just bought myself the Frankford Arsenal case trim and prep center and boy oh boy do I like that trimmer. It has probably cut my case prep time by 75%, I used to use the RCBS case prep center but it will be sold since the Frankford does the same plus a trimmer. For me it was worth the $270, maybe not for everyone though, I probably reload 5000 cartridges a year so speeding things up is worth paying for.
Just found this in my archives
http://www.xcr.ca/CustomReloadingData.numbers.pdf
Not all the data out there will cycle a semi auto so don't blame the rifle if some of them don't cycle.
I have some trailboss subsonic loads that I use in my bolt action 300BLK that are lots of fun but useless in my ACR 300BLK conversion. Wow, just realized I'm down to two rifles in 300BLK, I was up to four of them not that long ago
http://www.xcr.ca/CustomReloadingData.numbers.pdf
Not all the data out there will cycle a semi auto so don't blame the rifle if some of them don't cycle.
I have some trailboss subsonic loads that I use in my bolt action 300BLK that are lots of fun but useless in my ACR 300BLK conversion. Wow, just realized I'm down to two rifles in 300BLK, I was up to four of them not that long ago
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Congrats, let us know how it went!
Just found this in my archives
http://www.xcr.ca/CustomReloadingData.numbers.pdf
Not all the data out there will cycle a semi auto so don't blame the rifle if some of them don't cycle.
I have some trailboss subsonic loads that I use in my bolt action 300BLK that are lots of fun but useless in my ACR 300BLK conversion. Wow, just realized I'm down to two rifles in 300BLK, I was up to four of them not that long ago
This is awesome info. I'll be printing it out and taking it to Staples to have it laminated for conservation purposes.
On a reloading note my Hornady 300BLK dies came in yesterday and I picked them up on my way home from work (Yay!) they even had a Lee#4 shell holder for .223 so I picked that up while I was there (Yay again!) Got home and realized it's for priming, not for presses (Boooooooo) I really wish Lee would make their packaging a little more intuitive for those of us new to reloading. Make no mistake, it's my fault for not more thoroughly reading, but the press shell holders and primer shell holders are packaged almost identically and the couple places where I've seen them they generally share a display I'm sure I'm not the only person to have made this error, lol.
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