Mega Rad Gun Thread

[Club Sandwich]

Here's something I've been curious about for a while now.


How did Colt decide to switch from a 5-round cylinder in the Colt Paterson revolver, to the 6-round cylinder that became standard on later Colt wheelguns and just about all of their competitors?

the larger frame the Walker had allowed a larger cylinder made on the same tooling with just a new index notch at 60 degrees of rotation when cutting a bore into the cylinder while keeping enough steel (in theory) between chambers for the .44 ball on top of ~60gr of powder. this proved a little too ambitious with the metallurgy available at the time and Colt walked it back to 50gr recommended after having enough of the Walker revolvers need repair from kabooms and chain fires (leading to lard and wax seals, et c). from what my big Colt Book of guns says, it was a step to secure further military contracts with the Navy and Army as well with a similar frame, but scaled down for .36 caliber. this retained the 6 shot cylinder and better metallurgy saw these also get slimmer too (Pocket Percussion, Dragoon, et c).

note that 7, 8, 9, and 10 shot revolvers were around at the time as well and the advantage was mediocre considering loading gates and fixed cylinders were annoying to reload and carrying spare cylinders wasn't practical in a fight; often extra guns were carried, but this had logistical and cost issues too, not to mention the upper limit of reasonable one-handed frame size before it became too awkward to holster and carry.

so a slightly bigger caliber (.38, .41, .44, .45, et c), and one more shot was a decent middle-ground i think.

 

[Pretend To Imagine]

but to your specific problem: the spec for the barrel nut should be about 35-75 in-lbs. not ft-lbs.

I’ve always seen 30 ft lbs be the minimum for an AR 15 barrel nut. Aeros spec is even higher: https://support.aeroprecisionusa.com/hc/en-us/articles/14130432684951-Torque-Specifications

I’ve installed many barrel nuts to 30 ft lbs or more and not had an issue removing them. The TDP is to tighten to 30 ft lbs and then tighten to index the gas tube without exceeding 80 ft lbs IIRC.

 

[WelperHelper99]

SGAmmo has "okay" pricing (~55cpr) on brass-cased 7.62x39 if you're looking to buy in bulk. Free shipping on orders over $200 helps take the edge off a bit

Cool. Maybe in the future when that's more financially viable.

"PPU" Is Prvi partizan, they're known for making good stuff, cheaper than WWB, so skip the middleman and buy it their boxes instead.

Neat.

Ah I see. Well that's good to know about PPU. Just ordered two more boxes lol.

PPU shouldn't be magnetic. They also make decent hunting ammo in 7.62x39.

Good to know about the magnetism, it's range friendly, noice.

Meanwhile I'm thinking of building out something set up for subsonic 7.62x39. Possibly based on the Howa 1500 Mini action in a lightweight chassis, haven't figured out the chassis part yet.

I've thought of getting a bolt action for subsonic 7.62x39mm, but I keep coming back to me already having a SKS, which is already decently equipped for hunting, though not quiet shooting.

Would like a AK sometime though. Detachable 30 round mags sound cool, and I get to share ammo with my SKS. Maybe even build a AR in 7.62x39mm like my brother in law has. I love this round man, even with the price hike:

It's solid, dependable, absolutely fucks barriers, and the recoil is mild all things considered. The range is a bit shit compared to 5.56, but you get raw power in return.

 

[WhoBusTank69]

the spec for the barrel nut should be about 35-75 in-lbs. not ft-lbs.

If you're right someone done goofed and the entire consumer-side of the industry is convinced it's supposed to be ft-lbs

 

[Club Sandwich]

I’ve installed many barrel nuts to 30 ft lbs or more and not had an issue removing them. The TDP is to tighten to 30 ft lbs and then tighten to index the gas tube without exceeding 80 ft lbs IIRC.

If you're right someone done goofed and the entire consumer-side of the industry is convinced it's supposed to be ft-lbs

actually i had to second guess this, since it's been a long time since i've wrenched a barrel nut and a lot of the free floats aren't torqued on and are clamped or use a jam nut. from my old Colt manual, it's 35 ft-lbs, then rotate to the next notch for the gas tube exactly as mentioned. goes to show going off memory isn't the best thing to use, and that's my fault. i've edited the post a bit to note the correction and keep the mistake there as well.

i did find out that the barrel nuts seemingly do vary a bit as MWI says 40ft lbs max, JPE has theirs at 20 ft lb, Geissele rails have an 8 ft lb spec, and PRI has another at 15 ft lbs - these seem to depend on the material and how thick or thin it is, probably to prevent them from being over tightened, crushed, or having the threads destroyed on aluminum or magnesium rail. interestingly i can't find any clamp values for a lot of the clamp-on free float rails.

still, if that barrel nut is coming off, you can try the suggestion to tighten/loosen after some heat or alternatively cut it off.

 

[Lord of the Large Pants]

but to your specific problem: the spec for the barrel nut should be about 35-75 in-lbs. not ft-lbs.

With the greatest of respect: Are you sure?

I looked up the torque specs for a standard AR-15 barrel nut. Here are a few random pages. All of them are measured in ft-lbs.

https://ar15sport.com/ar15-torques-specs/

https://www.snipershide.com/shooting/threads/ar-15-barrel-nut-torque.237538/

https://www.ar15.com/forums/AR-15/Daniel-Defense-Barrel-nut-torque-specs-/118-726240/#

I found nothing that measured it in in-lbs. Now the M4E1 uses a non-standard barrel nut, so I looked that up specifically.

https://www.aeroprecisionusa.com/ar15-m4e1-enhanced-upper-receiver

The specs tab says: Barrel Nut Torque - 55 ft-lbs

One other small piece of evidence of it being ft-lbs is that the proprietary wrench adapter they included has a 1/2" square drive. A quick look on Amazon and I can't find any in-lbs torque wrenches with a 1/2" square drive. They're all ft-lbs.

If you're right, then the manufacturer spec lied to me, and I can blame them.

if you torqued to 55 ft-lbs, this is over 650+ in-lbs and you may have stretched the threads or cross threaded the aluminum receiver with the steel barrel nut (and these are fine thread too, so less forgiving of crazy torque values). be very very specific in remembering if you had an in-lb torque wrench, if you just mongo'd it on there with your arm and called it a day, or if you used a ft-lb torque wrench. a grown man can produce around 50 ft-lbs with one arm and an 8" spanner wrench, about half a again liquored up and two handing it.

I still have the wrench, and it's ft-lbs. I also remember doing a specific calculation to account for the length of the wrench so it wasn't overtorqued because of that.

I can believe I overtorqued it a little, but I'm not a strong guy (even less back then) and I don't think I'm psychically capable of overtorquing it by a factor of 5. I don't remember it being THAT hard to get on, at least.

if you did this, one option is to put some heat on the barrel nut (and aluminum flashing on anything you don't want to get hot) and heat the barrel nut and alternately tighten and loosen to work it a bit. this might take an hour or more. another option if you get no luck is to cut it off with a burr tool or dremel and cut off wheel and a steady hand. you don't need to cut all the way through, but enough to snap the nut with a crow's foot and breaker bar. the important bit here is your upper and barrel, not a $10 barrel nut.

If all else fails I'll look at doing this. Thanks.

EDIT: Woops, took me so long to write this that you already responded. Durr.

 

[WhatInTheActualFuck]

actually i had to second guess this, since it's been a long time since i've wrenched a barrel nut and a lot of the free floats aren't torqued on and are clamped or use a jam nut. from my old Colt manual, it's 35 ft-lbs, then rotate to the next notch for the gas tube exactly as mentioned. goes to show going off memory isn't the best thing to use, and that's my fault. i've edited the post a bit to note the correction and keep the mistake there as well.

i did find out that the barrel nuts seemingly do vary a bit as MWI says 40ft lbs max, JPE has theirs at 20 ft lb, Geissele rails have an 8 ft lb spec, and PRI has another at 15 ft lbs - these seem to depend on the material and how thick or thin it is, probably to prevent them from being over tightened, crushed, or having the threads destroyed on aluminum or magnesium rail. interestingly i can't find any clamp values for a lot of the clamp-on free float rails.

still, if that barrel nut is coming off, you can try the suggestion to tighten/loosen after some heat or alternatively cut it off.

I seem to remember reading to lightly grease the threads, torque to 30 ft/lb and back off twice, then torque to ~35 plus whatever is needed for timing your barrel nut and have done that on all my builds (which have all been pretty easy to take the barrel nut off when needed). I do keep shims handy so I don't ever need to go too much over 35, though.

 

[ChampFantana]

the larger frame the Walker had allowed a larger cylinder made on the same tooling with just a new index notch at 60 degrees of rotation when cutting a bore into the cylinder while keeping enough steel (in theory) between chambers for the .44 ball on top of ~60gr of powder. this proved a little too ambitious with the metallurgy available at the time and Colt walked it back to 50gr recommended after having enough of the Walker revolvers need repair from kabooms and chain fires (leading to lard and wax seals, et c). from what my big Colt Book of guns says, it was a step to secure further military contracts with the Navy and Army as well with a similar frame, but scaled down for .36 caliber. this retained the 6 shot cylinder and better metallurgy saw these also get slimmer too (Pocket Percussion, Dragoon, et c).

note that 7, 8, 9, and 10 shot revolvers were around at the time as well and the advantage was mediocre considering loading gates and fixed cylinders were annoying to reload and carrying spare cylinders wasn't practical in a fight; often extra guns were carried, but this had logistical and cost issues too, not to mention the upper limit of reasonable one-handed frame size before it became too awkward to holster and carry.

so a slightly bigger caliber (.38, .41, .44, .45, et c), and one more shot was a decent middle-ground i think.

Thanks for the info Clubby!

 

[BallsMcLongDong]

I shudder think what we'd be if we didn't have sandwich grandpa's advice to fall back on every time someone says, "Hey I found this gun in an underground cave surrounded by the corpses of 43 vampires and one angel, can anyone tell me -"
"Here's a link to a 6th century text describing which type of goat needs slaughtered to load it, and a Vatican archive scroll translating Sumerian to tell you how to oil it."

 

[Club Sandwich]

I shudder think what we'd be if we didn't have sandwich grandpa's advice to fall back on every time someone says, "Hey I found this gun in an underground cave surrounded by the corpses of 43 vampires and one angel, can anyone tell me -"
"Here's a link to a 6th century text describing which type of goat needs slaughtered to load it, and a Vatican archive scroll translating Sumerian to tell you how to oil it."

senility is only kept at bay with gunpowder and cordite.

 

[Lord of the Large Pants]

Gentlemen, I have removed my nut. If you know what I mean.

I dripped some Breakfree into the threads and let it soak overnight. I carefully examined the Bev block, and while the point is taken about the flexibility possibly fucking up torque values, I think it's good enough for removal. It looks to me like the front of it slots into the starburst thingies (the technical term) on the barrel. Now I'm no gun scientist, but ol' pa told me when I was a young'n that barrel steel can't be bent by God 1 and God 2 put together. Since it looks like that's where the force is being exerted, I decided to give it a shot. I put a foot long piece of steel pipe on my wrench and VERY carefully cranked the nut (phrasing), giving it somewhat more force than before. And eventually, something moved.

Now I'm going to do what I went in there to do, clean it VERY thoroughly, and put it back together with a lot less aeroshell. Probably wait until I get that steel rod since I already ordered the damn thing...

Thanks homies.

 

[Pretend To Imagine]

Gentlemen, I have removed my nut. If you know what I mean.

I dripped some Breakfree into the threads and let it soak overnight. I carefully examined the Bev block, and while the point is taken about the flexibility possibly fucking up torque values, I think it's good enough for removal. It looks to me like the front of it slots into the starburst thingies (the technical term) on the barrel. Now I'm no gun scientist, but ol' pa told me when I was a young'n that barrel steel can't be bent by God 1 and God 2 put together. Since it looks like that's where the force is being exerted, I decided to give it a shot. I put a foot long piece of steel pipe on my wrench and VERY carefully cranked the nut (phrasing), giving it somewhat more force than before. And eventually, something moved.

Now I'm going to do what I went in there to do, clean it VERY thoroughly, and put it back together with a lot less aeroshell. Probably wait until I get that steel rod since I already ordered the damn thing...

Thanks homies.

The problem with the bev block is you can break the receiver because the only thing keeping the receiver from spinning with the barrel nut is the index pin on the barrel extension.

You removed the barrel to clean it? Seems really unnecessary.

 

[WhoBusTank69]

senility is only kept at bay with gunpowder and cordite.

Add some guncotton for fiber intake.

 

[Lord of the Large Pants]

The problem with the bev block is you can break the receiver because the only thing keeping the receiver from spinning with the barrel nut is the index pin on the barrel extension.

You removed the barrel to clean it? Seems really unnecessary.

No, I removed the barrel because I did something stupid that I don't want to talk about.

 

[Club Sandwich]

the only thing keeping the receiver from spinning with the barrel nut is the index pin on the barrel extension.

the BEV block has a steel barrel extension insert for the locking lugs and also takes up space on the interior of the upper receiver. it's not the hinge pin taking all the force.

 

[Pretend To Imagine]

the BEV block has a steel barrel extension insert for the locking lugs and also takes up space on the interior of the upper receiver. it's not the hinge pin taking all the force.

View attachment 6562429

The bev block holds the barrel extension, but it doesn’t look like it prevents the upper from trying to rotate with the barrel nut. The index pin on the barrel extension is what is stopping the upper from moving, and all that force is put on the notch for the barrel extension in the upper. The pin can break or damage that notch.

 

[Legato]

The bev block holds the barrel extension, but it doesn’t look like it prevents the upper from trying to rotate with the barrel nut. The index pin on the barrel extension is what is stopping the upper from moving, and all that force is put on the notch for the barrel extension in the upper. The pin can break or damage that notch.

Ive used it for torqueing on muzzle devices so I dont see why it wouldnt work for a barrel nut.

 

[Club Sandwich]

but it doesn’t look like it prevents the upper from trying to rotate with the barrel nut

a reaction rod doesn't prevent the upper from rotating either soi'm not sure what you're getting at.

the BEV block does do a pretty good job of preventing the upper from rotating with installing or uninstalling a barrel nut. the BEV block prevents the upper from rotating with multiple contact points (hinge pin, charging handle journal, the interior BCG raceway) as well as engages the barrel extension to positively hold the barrel in place for muzzle device work. it isn't the "index pin on the barrel extension is what is stopping the upper from moving", the rest of the BEV block's features do as mentioned, and "all that force is put on the notch for the barrel extension in the upper" isn't true, as the force is both spread along a very large area with multiple points and the amount of force needed to break off the steel pin against the journal's lip or completely tear off or shear the upper off the BEV block is very far in excess of what is reasonable for assembling the barrelled upper.

a reaction rod holds the barrelled upper in position so you can torque down the barrel nut, however it does this by holding the barrel in place - it doesn't interact with the upper and the upper is free to move as it wants to. it is in this situation where it's only the indexing pin that is holding the barrel in position because there is nothing actually holding the upper in place with this method. and again, a reaction rod does this well enough that you can torque a barrel nut without too much issue.

Ive used it for torqueing on muzzle devices so I dont see why it wouldnt work for a barrel nut.

originally, a reaction rod wasn't intended for working on receivers (although you can do so purely to hold an assembled receiver in a vise if you're doing muzzle work or installing a free float, et c) because it isn't positively holding onto the receiver at all. a reaction rod only holds the barrel in place via (in an AR's case) the barrel extension's locking lugs and if it wasn't for both the indexing pin on the barrel extension and the clamping force of the barrel nut, you can freely spin the upper/barrel nut assembly on a reaction rod. reaction rods are generally for working on muzzle devices or similar so you aren't trying to screw on a flash hider on a barrel that is passing that torque through the upper receiver into the vise. bypass the upper receiver entirely and hold the barrel in place when doing that sort of work to avoid problems.

a reaction rod for a G36 or SCAR works the same way, it's for "clamping" the receiver and barrel together with the barrel retaining nut or breaching nut and adding on a muzzle device, installing the gas block, et c without disturbing the receiver at all and not transmitting force through the receiver to the vise - the reaction rod directly takes force from the barrel to the vise bypassing the receiver for the most part.

 

[WhoBusTank69]

View attachment 6555384
I didn't want another project, I was taking a break

I can't tell if this is the crap slim handguard or what, any (Bundes)wehraboos know which one that is? Also wondering about the gas tube being exposed, and if I should just go full comfy and get a wide handguard instead.

Sidenote: It's been a decade and change since I looked up the wide G3 handguards, people are fucking gay. Three hundred dollars for the ability to hold a G3 without burning yourself after two magazines is sad. Step up your game PTR, nobody likes the skinny handguards except people that have never held the good ones.

 

[Club Sandwich]

I can't tell if this is the crap slim handguard or what, any (Bundes)wehraboos know which one that is? Also wondering about the gas tube being exposed, and if I should just go full comfy and get a wide handguard instead.

Sidenote: It's been a decade and change since I looked up the wide G3 handguards, people are fucking gay. Three hundred dollars for the ability to hold a G3 without burning yourself after two magazines is sad. Step up your game PTR, nobody likes the skinny handguards except people that have never held the good ones.

i don't really recognize the hole pattern, they almost look like SLR / L1A1 handguards kinda, but they do appear to be cut down G3 wide handguards with the bipod locking spring that i guess someone cut some slots into.