Help me find something...

[KyleC]

There used to be a link to a chart that a member(Dellet, or Certifiable, I think) had created showing lighter weight subs and powders and whether the combo cycled or not.

I could've swore I saved it but can't find it, or the link, any longer. If anyone could post the link or send it in a pm, I'd really appreciate it. It has a wealth of knowledge

[fancygunz]

There used to be a link to a chart that a member(Dellet, or Certifiable, I think) had created showing lighter weight subs and powders and whether the combo cycled or not.

I could've swore I saved it but can't find it, or the link, any longer. If anyone could post the link or send it in a pm, I'd really appreciate it. It has a wealth of knowledge

Is it this sticky? viewtopic.php?f=141&t=86656&sid=3eee339 ... 2dab5fe5d0

[KyleC]

I don't think so. I looked through that o r yesterday and didn't see what I was looking for, but I'll look again. Thanks for taking the time to help!

[popper]

I tried with 100gr plinkers and pistol powder, neat but no cycle in 10" pistol. Consensus appears to be the same for mid weight subs, yes they shoot but don't cycle. Unless HP38 style, not enough gas and even 2400/unique doesn't work.

[ozleux]

viewtopic.php?f=141&t=96399
This may be what you're looking for

[TRshootem]

Two things appear in that body of work/data: There are a couple of powders that just plain work, with the mid weight bullets to the heavies. There are some who fuss about how loud or dirty a particular powder is etc. If you have scanned that information, 1680 just plain works across a wide selection of bullet weights. Note that in that info is a another powder or so that provide good function. Another nugget of knowledge on this site, one can determine that 100 gr bullets are fine for supers, but likely never worth the time trying to reinvent the gas operation of a AR15. However, if shooters want to enjoy tinkering with light bullets and subsonic loads, use bolt actions, single shot and/or running the charge handle like a bolt.

With all my 50 plus years as a hand loader, this site is a wealth of information to folks like me or a newly minted gun crank. Bottom line, the learning curve is shorter by spending some quality time searching threads, not only here but a couple of other sites worthy of your time. That darn thing called Google will answer your searches with lots of reading. Have a pen and paper handy for your valuable notes.

[dellet]

Two things appear in that body of work/data: There are a couple of powders that just plain work, with the mid weight bullets to the heavies. There are some who fuss about how loud or dirty a particular powder is etc. If you have scanned that information, 1680 just plain works across a wide selection of bullet weights. Note that in that info is a another powder or so that provide good function. Another nugget of knowledge on this site, one can determine that 100 gr bullets are fine for supers, but likely never worth the time trying to reinvent the gas operation of a AR15. However, if shooters want to enjoy tinkering with light bullets and subsonic loads, use bolt actions, single shot and/or running the charge handle like a bolt.

With all my 50 plus years as a hand loader, this site is a wealth of information to folks like me or a newly minted gun crank. Bottom line, the learning curve is shorter by spending some quality time searching threads, not only here but a couple of other sites worthy of your time. That darn thing called Google will answer your searches with lots of reading. Have a pen and paper handy for your valuable notes.

If I had to only use one powder for 300 blackout, it would likely be 1680 or Shooters World Blackout. It’s dirty and louder than it needs to be for subs, but it’s tolerable. Same with light supers, 110’s end up velocity challenged.

With that said, 16” carbine gassed rifles without a suppressor can easily cycle 175 grain bullets from 1000-2000 fps. 168’s are tricky without a suppressor and 150’s become a party trick with no other purpose than bragging rights.

It’s really not the gas system of the rifle that is hard to understand and work with, it’s a fundamental misunderstanding of internal Ballistics. Popper made a comment a few posts up about 100 grain bullets and cycling problems with mid weight subs, that kind of highlight this. His thinking is backwards. The answer is not a faster powder, it’s slower. The answer to almost all cycling problems that are ammo related boils down to a peak pressure that is too high, resulting in a low muzzle pressure. If you understand how to manipulate internal pressures, all your problems go away. If you don’t, then start drilling ports, cutting coils, buy ultra light buffers and prepare for frustration.

An example of how counter intuitive this is would be my 125 SST subsonic load that is full function subsonic is an 8” suppressed AR, uses 11.5 grains of 4227. Almost 2.5 grains more than the recommended load for a 208 Amax as a sub.

The load data linked above from certifiable and some of his others posts are the gold standard on this forum. He has helped thousands of people save thousands of dollars. Probably some of the best data on the web for the cartridge.

[TRshootem]

I sure appreciate you Dellet, as well as all the fellow enthusiasts who share their adventure. I'm sorry to report that I have not dove into the Shooters World stuff, I seemed to get side tracked with other projects. Healing up from an injury to my right shoulder, I'm back at the load bench. Passed through your part of the world, just not a good time to stop for a quick visit. Thanks again, on to more gitter done stuff before winter arrives.

TR

[popper]

Problem with the slow powders is finding ones that burn properly. Without QL or other it is difficult for newbies to get started. I just had some plinkers to play with in pistol gas. I shoot 150 & 185 in carbine gas all the time, no problem. Personally without a can I have no use for subs. 4895 can be used but why? Curious as to why someone wants to shoot light weight subs.

[dellet]

Problem with the slow powders is finding ones that burn properly. Without QL or other it is difficult for newbies to get started. I just had some plinkers to play with in pistol gas. I shoot 150 & 185 in carbine gas all the time, no problem. Personally without a can I have no use for subs. 4895 can be used but why? Curious as to why someone wants to shoot light weight subs.

Because 22’s are fun.and I can get the recoil of a 300 Blackout down to just about that level, maybe less

Slow powders tend to be very dirty, then with light powder charges for subs, they just get worse. So the next best thing to do is take a fast powder and slow it down. 4227 is a magnum pistol powder.

There are a lot of reasons to manipulate burn rates. Cycling an AR is just the most common reason with this cartridge. A high peak pressure gives the most efficient burn of the powder and will have less muzzle pressure. That will reduce recoil, but leave less pressure to cycle the action. This is why seating depth of the bullet effects cycling reliability.

I have done a lot of things with this cartridge simply because I saw a way to see visible result from certain ballistic theory. Getting a light bullet to cycle subsonic will test your knowledge more than believing people who tell you that a subsonic 110 grain bullet will never be able to cycle in an 18” carbine gassed gun without major modifications. Once I had that one figured out, a 10” carbine gassed SBR was no problem. It’s lighter recoiling, quieter, less gassy and less flash than any pistol gassed gun of the same length barrel. If I had listened to the folks that said neither are possible, instead of just finding a way to do it, I would have never figured out a way to tame the recoil of a 9 pound 45-70 shooting 350 grain bullets 2000 fps.

Kind of a long winded way of saying keep experimenting. The key is figuring out how to change the burn rate to your advantage. 1680 is loud and dirty for subs. I won’t use it, too many other choices, but it will cycle almost anything. Put it under a 150 grain or heavier super and it’s hard to beat for velocity and accuracy. It’s clean quiet and efficient. The difference is the quality of the burn of the powder.