I tried out some of my 300BLK 220gr SMK loads with my SDN-6 yesterday.

I had my aimpoint zeroed at 25 meters with these rounds when I shot them unsuppressed to check stability before, and this time I put my 8" steel plate target at 100 meters. I held the aimpoint's dot at the top edge of the plate and hit the plate consistantly with ease. The round was quiet, and I even tried them without hearing protection on with no problems. They were a little louder than I thought they would be. Seemed like it was from gas exiting from the ejection port. I may try a heavy buffer to see if that keeps the bolt closed a little longer to let the gas pressure drop a bit before opening.

I then shot them at the 100 meter steel silhouette with about 3 feet of hold over. They hit every time, and they hit like a hammer.

I tried a few at 300 meters too just to goof around and gave about 6 feet of hold over. I was surprised to hear the hits at that distance as well.

I couldn't use the chrono since it was totally overcast out. Last time I tried under those condiditons I got really spotty results.

They functioned flawlessly and held the bolt open after the last shot every time. I guess I need to go ahead and make some more of these rounds now.

Load data used:

Converted LC brass
10.9gr of AA 1680
SMK 220gr bullets
CCI 400 primers.

Rifle used was a 14.5" barreled AR with pinned AAC Blackout FH. Carbine length gas system with standard carbine buffer and spring. Suppressor was AAC 762SDN-6.

That's GREAT news, Chris, thanks!

I have carbine gas on my rifle, and plan on getting the same can you have (going to start paperwork after the holidays).

I was a bit worried about proper cycling suppressed with carbine gas, since most everyone else uses pistol gas.

Do you have an adjustable gas block? I have a Syrac Ordinance on mine (planning ahead)... Might help control the amount of gas for you.

quote:

Originally posted by exx1976:
Do you have an adjustable gas block? I have a Syrac Ordinance on mine (planning ahead)... Might help control the amount of gas for you.

No, I don't have an adjustable gas block unfortunately. And with the pinned flash hider, I am kind of stuck with what I got. That's why I am thinking of trying the heavy buffer. I also have a JP spring kit in my trigger group, and I think I might also try swapping the hammer spring out with a stock spring to stiffen up the hammer thus slightly retarding the bold carrier's reward travel.

Depending on what the Chrono shows with the can, I may back the powder down a tenth or two also. It's good to have options.

https://sigforum.com/eve/forums...0601935/m/6580009933


Just figured I'd link this here for the 300BLK crowd in case you don't frequent the rifle section. Definitely check these out. Much easier to load than PMags.

quote:

Originally posted by C Swimm:
They functioned flawlessly and held the bolt open after the last shot every time. I guess I need to go ahead and make some more of these rounds now.

That is great your shooting went well. The 220SMK is really accurate once you know its drop at each distance.

For those of you using a Dillon press - if you are loading flat-base projectiles like the 125SMK, try out the C powder funnel instead of the one labeled "7.62x39/300Whisper" (AK). It is like their pistol powder funnels, and has a built-in flare. Adjustable, just like the pistol funnels.

I just put mine in (it got here a few days ago, but bullets just came today), and adjusted it to BARELY flare - same as my pistol setups. You literally have to feel to make sure it's there. But, the bullets seat SO much easier now, and now little copper shavings on my press (every so often it would shave the corner of the base on a bullet).

Just whipped out ~150 rounds, and no problem. w00t!

This message has been edited. Last edited by: exx1976,

Thanks. I was looking at setting up my 650 for 300 BLK. I was going to try the 30 carbine powder funnel. Sounds like the 7.62x39 is exactly what I was wanting. I figured a slight flare would be necessary for the flat base bullets. Thanks again.

So much fail I decided to remove it. LOL

This message has been edited. Last edited by: exx1976,

Yup got the Lee FCD already and an extra toolhead ready to put together. I did the first batch on my Redding single stage. I am going to chrono the rest of that batch when the weather permits, and then I think I am ready to go into full production. I just need to order the powder funnel.

I am hoping I get some gift cards for Christmas so that I can order another powder dispenser with that funnel.

I figure for now I will do the case prep on the single stage. Sizing die for now, then trip on my Forster trimmer with power drill set up I made. I have a 30 cal 3-way cutter for that too.

Eventually I will get the trim die and start bulk trimming with my Dillon RT1200 on the single stage with an extended shell holder. Later I will get a shaved tool head and set up a case prep tool head for the 650 to size, trim, and Lyman M die all in one process. Like I do for 308 and 223 now.

Do you use the Dillon shell feeder? I read that for 300BLK it is best to use the small pistol plate with 2 spacer washers. Have you tried this? Any suggestions?

I just checked the Dillon web site they list the powder funnel as "7.62x39/300Whisper/300Savage"

Looks like they figured it out too. Thanks again.

Oh, which case feed adapter?

I heard some guys using the .223 one but it has hang-ups since the opening is too long for 300blk, and othes trying the 380 one and cutting the slot longer. Do you know if there is one that is already the right size?

They must have figured it out recently, I ordered mine last week and it still only said "AK". LOL

That's cool though.

As for the case feeder, sorry, for me that's my right hand. I only have a lowly 550. It works for me though.

That is good news. Have to check my funnel and see which one I have on the 550. I think I recall getting it at the LGS, so who knows what they had on hand. I haven't worked up any flat base yet, but did find a box of the Berger 115 fbhp to test, so this is timely. Happy holidays everyone!

quote:

Originally posted by Prudence:
That is good news. Have to check my funnel and see which one I have on the 550. I think I recall getting it at the LGS, so who knows what they had on hand. I haven't worked up any flat base yet, but did find a box of the Berger 115 fbhp to test, so this is timely. Happy holidays everyone!

Berger? I honestly didn't think this cartridge was capable of good enough accuracy to warrant feeding it such expensive bullets. I've always looked at this cartridge as more of a battle-rifle/run-n-gun type, and was plenty happy with MOBeerCan. Please post some targets when you get those loaded up!

Hah! Will do, once the deep freeze passes I can get out without losing any appendages...effing -5 crap is getting old, but you are getting the same as we are...so at least misery has company!

I hear ya. It was -2 when I woke up this morning at 0700, and it's gotten colder since. Ugh.

Come on, April!!!

I picked up some 115gr Berger HPs recently as well. Got some Li'l Gun powder to push them out with too. Looking forward to seeing what they can do.

quote:

Originally posted by C Swimm:
I just checked the Dillon web site they list the powder funnel as "7.62x39/300Whisper/300Savage"

Looks like they figured it out too. Thanks again.

Thanks for the info.

I decided to order this powder funnel tonight to give it a try. The flat base bullets I have loaded are the only ones that don't drop perfectly into my Sheridan Case Gauge after loading and I think it is because the flat base bullet going into the cartridge is causing a very slight case bulge. Even though they don't perfectly fit in the gauge, they have functioned fine in my rifle.

I will see how these do with trying the new funnel when I get it.

Cabela's has Accurate 1680 in stock.

https://sigforum.com/eve/forums...0601935/m/9930030143

You won't be stocking up on it from them (unless you're crazy), but at least you can get 2 pounds for load development and to hold you over until you find 8 pounders.

GENTLEMEN:

Everglades has once fired Lake City blanks in stock for $52/k, $50/k for 2 or more. Since we are already cutting it down, it makes no difference that the mouths/necks were at one time crimped.

For anyone that has concerns about the brass: There are several comments on the site about people that have already used it for blackout brass. Additionally, there is/was a LARGE thread on arfcom about a guy that used blank brass for regular AR brass - he just cut the crimps off, and trimmed/chamfer/debur like normal, and reloaded and shot them until they died. He had no issues with it.

http://www.evergladesammo.com/...ass-1000-pieces.html

I have 2k pieces on the way to me right now.