300blk pistol vs rifle for supers

[Odysseus1911]

Debating selling my 16" 300 blk to replace it with a suppressed pistol length 300blk.

Question is: running supers, how much velocity are you going to lose going from 16" to 7.5"?

 

[hlee]

Sellier & Bellot 124 gr FMJ load has a published velocity of 2165 fps. My magentospeed says it is running at 1936 (avg) out of my 8" Odin Works barrel. Hornady 110 gr Vmax load has a published velocity of 2375 fps. It is running at 2184. So, figure ~200 fps loss.

 

[Odysseus1911]

Outstanding!

That's not much loss at all for such a barrel reduction.

 

[Darqusoull13]

My loads went from ~2400 FPS with a 110 Barnes in a 16" to ~2200 FPS in a 10.5"

For a blackout, short barrels are amazing . My new favorite hunting gun.

 

[Strykervet]

Sellier & Bellot 124 gr FMJ load has a published velocity of 2165 fps. My magentospeed says it is running at 1936 (avg) out of my 8" Odin Works barrel. Hornady 110 gr Vmax load has a published velocity of 2375 fps. It is running at 2184. So, figure ~200 fps loss.

He's actually spot on, I have a 8.5" Noveske bbl. and a 16" AAC and I get that on the chrono.

For best results, drop the weight to 110's or 115's if you can and you retain a bit more velocity. With a 16"bbl. you get ~AK velocities using 125's and in an 8.5 you can retain much of that velocity by dropping to a slightly lighter bullet.

Anyway, wanna say the 110's or 115's out of an 8.5 are still going ~2200. I don't have any of my data handy though, sorry.

Don't do the 7.5, it's just too short. 8.5 is ideal and Noveske makes a bad motherfucker, period. They're my goto for SBR barrels. Been ~1MOA all day long and they cycle like they're supposed to, will handle supers or subs, suppressed or not and not jam up.

I own a few of these so BTDT. If you REALLY want a killer PDW, check out this build:

It's actually an SBR but same deal. Uses TBAC cans, usually the Ultra 5. This thing is smaller than most at ~20.x inches. Almost 21" I think. I've had grips, lights and optics on it but I have another SBR pimped out with all the sandbox gear and a CTR stock. This one got basic irons for fast acquisition and it's damn fast. What you want in a PDW. And I can always clip a Surefire grip light on that bottom rail if I want but I usually keep it covered with a KAC rail cover. The PRI triangular FF tubes, you almost never see 'em but they're very comfortable. This thing is accurate and it's very reliable. Not to mention fast with that 3G trigger. The straight grips Mapgul makes for short rifles are just great too IMO.

If you have the coin though, a Sig would be a better buy IMO with the folding stock and all. That or maybe a BT APC .300, I bet those will only go up in value too.

 

[Longshot85]

Will you be running suppressed?

If so is it a commercial can or form 1 ?

There's A LOT of benefits of having a form 1

I mention this because of unburned powder being hard on cans when going shorter than 10 inches.

I have a 10.5 in Nordic Conmponents 1:8 barrel on my project I'm about to finish up. I will be running a form1 6 inch titanium can with mostly Ti baffles.

It may be a little bit but I'll follow this thread and post data from a magneetospeed.

Pic .......just because.....project still in the works

 

[Odysseus1911]

Definitely plan to run suppressed. The intention is to have a rifle that can excel at home defense and CQB, but could still take deer sized game in a pinch.

I get the advantage of form 1 being able to repair/replace yourself, but how do these kits perform sound and weight-wise compared to a top tier suppressor like TBAC?

 

[Longshot85]

Surprisingly enough, my other form 1 that's the same size as my buddy's TBAC (9 inches long and 1.5 inch diameter) sounds almost identical. The tone is slightly different but sound suppression is the same (this is to human ears not the official multi thousand dollar meter.)

The first time I shot it on my 6.5CM I had two buddies spotting for me. I had zeroed the rifle unsuppressed with factory 140AMAX at 100 yards on a paper target. I installed form1 can, held same point of aim and sent 3 rounds. There was some point of impact shift as with most cans BUT there were 3 holes touching each other. I then rezeroed rifled and banged steel with great accuracy as far as we could shoot that day which was 600 yards.

I am not much about bragging about "one time I shot 0.2 MOA.....blah blah blah....." but I do think it's relevant since you seem interested that I mention it's capability. Basically the rifle as a system setup can shoot as well as I can. When trying to shoot groups on paper.......yes it's definitely 0.5 MOA capable for sure and lots of time better than that but not always (insert human error.)

If you want to hunt, works great for that too. I have shot several deer with this setup. Most notable is prolly the 632 cold bore shot out of a tree stand.....one shot and dropped like a ton of bricks.

My buddy (and myself as well) can absolutely vouch for TBAC and their product. Their stuff is absolutely top notch. There new cans look even better. One day I plan on snagging a .338 Ultra. In no way, form, or fashion am I saying my form 1 is up to par with them. I am simply stating that if enough attention to detail is applied the end results a form 1 can yield is probably far better than most would expect.

I run SD tactical muzzle brakes that have external threads. I have a muzzle brake on my .22LR bolt action, .223 Wylde SPRish build and my 6.5CM.......I have been bouncing the 9 inch form 1 around for years. The SPRish build can shoot 0.5 MOA with 77 grain IMI (slightly better with handloads using XBR 8208 and 77 gr TMK.) The .22LR is absolutely epic to shoot with subs and my young son likes shooting it better than any other air rifle or .22 without a can.

8.6 creedmoor will be out one day.........form 1 = easy solution

Commercial can = buy a .338 can

Here's last 4 rounds I had in my magazine fall 2017 one day when I decided to shoot a group at 1100 yards after having fun 600-850 and just watching rounds fall nearly on top of each other.

Another pic to show why tracking cold bore shift matters

 

[ScarlettRed]

I would also caution going too short. I have a sig rattler canebrake with a 5.5 inch barrel and a tbac 30ba on it. I just started trying some different ammo and the best group I can seem to get is 1" at 50 yards. Most ammo seems to be 3-4 moa. This evening I shot 2 types of subs and was throwing keyholes all over the place. Scary. Despite Sig saying they will work, I ain't risking it. Another weird anomoly is even with the same grain bullets (110) the poi at 50 is crazy different between brands. I think I may have to pick up a 9" barrel If I want the gun to be more useful.

 

[hypno02]

I would also caution going too short. I have a sig rattler canebrake with a 5.5 inch barrel and a tbac 30ba on it. I just started trying some different ammo and the best group I can seem to get is 1" at 50 yards. Most ammo seems to be 3-4 moa. This evening I shot 2 types of subs and was throwing keyholes all over the place. Scary. Despite Sig saying they will work, I ain't risking it. Another weird anomoly is even with the same grain bullets (110) the poi at 50 is crazy different between brands. I think I may have to pick up a 9" barrel If I want the gun to be more useful.

You should contact Sig. My rattler is money. Solid 2moa out to 150yds with both S&B subs and supers.

 

[shoobe01]

I only have the .300 to run subsonic and suppressed. 10.5" on my SBR lower.

FWIW, here's the ammo I have shot so far, not all of which are subs. Got another half dozen loads I am slowly gathering (I don't reload for reasons), sometime will get to a big range day, then pick one to buy by the case and just /shoot/ the thing finally. I have too many projects

 

[mkollman74]

You should contact Sig. My rattler is money. Solid 2moa out to 150yds with both S&B subs and supers.

This is my experience as well.

 

[ScarlettRed]

I'm glad to hear the rattler has potential. Mine has been 100%, just not that accurate. I might have to hold on to it for a while as I might like to have it on hand during the current madness. Really cool gun though.

 

[Strykervet]

Here's another Noveske 8.5" bbl. No problem cycling supers or subs, they got their shit together on these barrels. ~1MOA depending, but that's the norm with their SBR barrels. The other thing is it'll ring a 12" plate at 200 as fast as I can pull the trigger, supers or subs. It's a bad bitch.

This one is a 10.5 that I've honestly never fired but it's the lightest and most svelte rifle I have. It was the ex's rifle and a factory Noveske build. I bet it's damn nice, maybe one day I'll shoot it. #75 Johnny Rifle:

TBAC 30CB9 works great, but I really like the Ultra 5 with these. It takes enough bite out of the bark to make it manageable and it keeps it short. However, the SDN6 was designed for this round and despite having a shitty mount it's actually a good can (well, it is if you have a good method of unfucking the mount situation, mine is to buy ten, fine the best one and send the rest back --much easier than polishing or refacing the bevel surface). Saker is a better 7.62 QD can though and since prices came down it's hard to beat. Omega 9k is another good buy, it works on 9mm too and is short like the Ultra 5 but steel so it can handle more abuse. The KAC can is the titties but it's too damn costly unless you already have an SR25, then it's not a bad deal.

I have a 16" rifle too but it's no more or less accurate than these and it only has slightly more velocity with the supers and I've clocked 'em myself. It makes a nice addition to the M4 family though and the ACOG is mapped to that barrel so that's a plus.

Another reason I'd go 8.5 minimum or longer is that the bullet barely stabilizes out of that as is and any shorter it's prone to wobble and fuckup the can. 5.5" would scare the shit out of me, cans are too much trouble to be farting around with like that.

A 10.5" w/5" can would be ideal, either an Ultra5 or an Omega9k, but there's nothing wrong with the 8.5"s either. I'd get a good barrel though because how they drill that gas port is everything with these barrels.

Good luck, it's one of those top 3 best rounds for an AR along with Grendel and 5.56 and everyone with a can should have an SBR'd Blackout (or a pistol if no SBR state).

 

[Longshot85]

Good stuff ^^

More form 1 pics

Brake and other components are from SD Tactical

 

[smacha538]

@NFAJohn

 

[NFAJohn]

Supers from a 7.5 are just expensive noise.....subs on the other hand are sill fun. I have a 7.5” 7 twist just for shooting subs and screwing around. I’ve been on guided hunts using 10.5” guns running 125sst and they killed hogs just fine on the first volley with well placed shots, runners took multiple hits to be downed.

 

[Longshot85]

Supers from a 7.5 are just expensive noise.....subs on the other hand are sill fun. I have a 7.5” 7 twist just for shooting subs and screwing around. I’ve been on guided hunts using 10.5” guns running 125sst and they killed hogs just fine on the first volley with well placed shots, runners took multiple hits to be downed.

Good to hear since I have my 10.5 inch build going.

Have you had a chrono on those 125 SST?

What ammo have you ran subsonic and any preferences?

Thanks

 

[NFAJohn]

Didn’t get to chrono the 125s, guns and ammo were supplied by the outfitter. He did say they were loaded with max charges of H110 and judging by the ejector swipe on the one spent on I looked at he wasn’t bsing. The were min of eye socket accurate at 50ish yards

As far as the subs go I started off running 208 amaxs over 11.5gr of 1680 and the were a ton of fun out to 200 yards. I want to say out of my 7.5” the we’re right at 1030fps and they did make a sonic crack out of a 16” bolt gun. Subs are the only time I started high in load development and worked down. When I’m short on time or 1680 is hard to get the S&B 200gr fmj load is cheap and shoots near the same poi as my hand loads.

 

[Yondering]

I also recommend against going as short as 7.5"; it does give up quite a bit compared to a 10.5", and even to a 9" barrel. You're losing ballistics and making it louder, just for the sake of an inch or two length that doesn't really matter. Personally 9" is the shortest I'm willing to go (and I do have a 9", not just guessing).

For subs it doesn't matter much, other than the shorter barrel is just louder, suppressed or not.