Lilja Short Barrel... New Poll

[cory]

WoW!! Where do I send my money?

I'll be collecting a deposit hopefully in the beginning of August. 25% if you're just buying a Nitrided Barrel. If you're buying an SLR gas block and/or Spikes upper/rail it'll need to be a little higher. (5%-10%) I'll be paying for them in full up front. I'll have to look at the numbers and figure that out.

Getting the Barrels Nitrided, they may have to be shipped to me afterwards for me to ship out unless I can figure something else out. If that's the case I'll ship everything at the same time.

[Bwild97]

Thank you Cory!

[Variable]

The reason Lilja doesn't do 1/2" twist is because they don't have the tooling. The tooling required costs a few hundred dollars.

If we can get a 25+ order here, Lilja will get the tooling to do the 7.5" Twist. However, it will cut into our additional discount.

Personally I don't mind paying a few more dollars to get the nominal twist rate. What do y'all think about it?

Well, I'd highly value Bill Alexander's input above all on it, but... If I were forced to choose between 1-7", 1-8", or pay extra for 1-7.5" twist, I'd likely choose 1-8" twist unless the cost difference was very negligible.

If Tex's 1-8.75" twist will stabilize the 160 grain bullet (yes, it's a 20" barrel, but he's loading subsonic-- so barrel length isn't really at play here because he's running the same speeds I was) , then we should be good to go with 1-8" twist.

Again-- I would much rather have Bill Alexander's opinion though. He'd be the subject matter expert by far on the Grendel cartridge in all different configs!

[BluntForceTrauma]

I, too, would like to see the slowest twist we can get away with. But maybe my technical understanding is flawed. I'm assuming we can squeeze out some "free" extra velocity with a slower twist, but I'm not sure if that assumption has been debunked or not.

Anyway, Bill A. almost always engineers for the worst-case, extreme military use scenario, as well as the worst-case Billy Bob Bozo abuse. Tests for sub-zero arctic use and sauna-hot tropical use and for those wanting to shoot both 85gr varmint bullets and 160gr round noses in their 10.5" SBRs. I'm not really worried about those extremes, you know?

Give me the best twist rate for an 11.5" or 12.5" bbl using Wolf 100gr FMJ and Hornady 123gr AMax and I'll promise not to load 160gr round noses.

[cory]

I, too, would like to see the slowest twist we can get away with. But maybe my technical understanding is flawed. I'm assuming we can squeeze out some "free" extra velocity with a slower twist, but I'm not sure if that assumption has been debunked or not.

Anyway, Bill A. almost always engineers for the worst-case, extreme military use scenario, as well as the worst-case Billy Bob Bozo abuse. Tests for sub-zero arctic use and sauna-hot tropical use and for those wanting to shoot both 85gr varmint bullets and 160gr round noses in their 10.5" SBRs. I'm not really worried about those extremes, you know?

Give me the best twist rate for an 11.5" or 12.5" bbl using Wolf 100gr FMJ and Hornady 123gr AMax and I'll promise not to load 160gr round noses.

I get that, but I do intend to load from 95gr to 140gr projectiles. I'd really like to hear Bill As thoughts on a 7" and 8" vs a 7.5" twist in a 10.5" to 12.5" barrel.

Maybe one of y'all that know him can point him to this thread.

[BluntForceTrauma]

Sounds like 7.5" twist would be best, then, if that's what Bill A. used in his 10.5". I suspect any velocity gain going to 1:8 is barely measurable, if any, so the point is probably moot. Heck, what twist did he use in his 14.5s? I'll have to dig it up but I seem to remember it's 1:7.5.

Yep, from AA's 2010 catalog the 16, 14.5, and 10.5 are all listed as 1:7.5, so I think it's safe to assume he'd use that on a 12.5".

[cory]

Sounds like 7.5" twist would be best, then, if that's what Bill A. used in his 10.5". I suspect any velocity gain going to 1:8 is barely measurable, if any, so the point is probably moot. Heck, what twist did he use in his 14.5s? I'll have to dig it up but I seem to remember it's 1:7.5.

Yep, from AA's 2010 catalog the 16, 14.5, and 10.5 are all listed as 1:7.5, so I think it's safe to assume he'd use that on a 12.5".

I don't think I asked my question correctly. I thought he'd say 7.5" was the nominal twist. My question was more how would a 7" or 8" compare, so we know if it's worth paying more to get the 7.5" twist. If it's not I'd be interested in what he thinks about a 7" twist.

[BluntForceTrauma]

Ah, I see; I didn't realize "half-twists" cost more. At any rate, I did ask Bill and he thought 1:7.5 would be the way to go with a 12.5". I said, "Couldn't you tweak it up to 1:8?" He said that, speaking for the 10.5" . . . at sea level . . . in cold weather . . . with a 140gr . . . you MIGHT have issues stabilizing. He said he could have used slower twists in the longer barrels, but they shot so well with 1:7.5, so why not? He could have, for example, used a 1:9 in his 18".

I asked about velocity gain relative to twist. "Bullocks!" He said that was postulated by some with more time on their hands than pressure-testing equipment. (Also, and Bill didn't say this but I know it's a factor, more velocity is gained by minimizing the rifling profile area than by the twist. I think the 6.8SPC experimenters failed to properly control for that variable and falsely attributed velocity gains to twist.)

[cory]

Please see Post #3 for an update. I was able to get some SLR gas tubes and charging handles added to the deal.

[txgunner00]

... I'll promise not to load 160gr round noses.

I won't make that promise...

[Variable]

I won't make that promise...

Me neither.LOL I'm too lazy and busy (crazy but true) to do much, but I'm hoping that the 160's will run better in a 12.5" bore for me. I want them to cycle reliably with Trailboss powder.



The donuts of death along with the ballistic telephone pole....

[cory]

I need to get a good count on who's in on this email, what everyone's preferences are and what other deals they'll be getting in on.

Please download the excel sheet at the following link and then email it to me at me.cory.m.clark@gmail.com (the email is correct, please copy and paste)

https://www.dropbox.com/s/vp66x3vvs9qgf1z/Feel%20for%20Interest.xlsx

I've also posted the link in the OP.

Thanks

EDIT: Alright it's good to go now.

[cory]

I screwed on my math with the Spike's Discount.



I forgot to add in the discount for not needing the barrel nut for the mil spec receiver.

[Kikn]

I don't want the barrel. Can I get in on the rest of the group buys?

[cory]

I don't want the barrel. Can I get in on the rest of the group buys?

The spikes yes.