Willbirds Aero/Sig Shorty 308

[jtallen83]

7 minutes ago, willbird said:

Preliminary measurements are showing me that I will need an 11-1/8" gas tube to end up right where we want to be.

Bill

This is the third different measurement listed for these barrels, granted we are talking 1/16th's of an inch, from a straight 11 inch to one at 11 3/16th inch. This is with the same Aero upper, starting to make me wonder if these barrels were QC rejects from Sig, hard to believe they would change up a piston system that often. 

[willbird]

To be fair I just eyeballed the gas block where I know the port lines up, and I marked length on the strong side with a black sharpie, I am going to cut a gas tube to try and I can take metal off with the lathe but have not yet mastered putting it back on ;-). 

I gambled on the 12" rail because I personally would prefer to not have the gas tube hanging out of the front end, could burn my hand during a meth head human wave attack ;-).

Pretty sure it will work out decent with Surefire Procomp 762 muzzle brake.

Bill

 

[jtallen83]

17 minutes ago, willbird said:

could burn my hand during a meth head human wave attack ;-).

Black Hills Gear can make you a rail cover to take care of the heat 

https://www.blackhillsgear.com/store.html#!/High-Temp-Nomex-Hand-Guard-Wraps/p/85656497/category=0

[willbird]

1 hour ago, jtallen83 said:

Black Hills Gear can make you a rail cover to take care of the heat 

https://www.blackhillsgear.com/store.html#!/High-Temp-Nomex-Hand-Guard-Wraps/p/85656497/category=0

Building 5 more identical guns and just rotating them until the wave is exhausted might work too ;-).

Bill

[willbird]

I took a Brownells mid length gas tube, cut off gas block end, lathe turned a filler plug, tapped it it, drilled the cross pin hole (304 sucks to drill hehe) drilled the gas port hole, and it all worked out OK :-). Final length was indeed 11-1/8". I used some random gas block I got somewhere. Will still order some custom tubes, mine is not perfect in spite of working.

Best group of the day was 5 in 2" with 4 within 1" ..that was with WW 180 grain power point ammo.

Function was nearly perfect...a few failures to lock back empty with Tula, the final buffer I need to put together will be a little lighter, I have a couple DSG-4201-0021 bodies and some Tungsten weights to add to one of them.

Lower as pictured including mag 52.8oz

Upper as pictured (will have muzzle brake added yet) 98.9oz

Total 151.7 oz  or 9lbs 7.7oz

parts list roughly in order of acquisition

$49 CDNN sig 716 barrel that started it all

Aero M5E stripped lower on sale from Brownells

This lower build kit here from PSA

https://palmettostatearmory.com/psa-moe-ept-pistol-lower-build-kit-with-sb-tactical-pdw-brace-black-5165447568.html

Aero M5E1 upper and 12" handguard

Aero takedown and pivot pins

Aero extended mag release

Brownells mid length gas tube

random generic gas block I got from somwhere

Borrowed parts (bad habit but I just could not wait for the brown truck)

Sprinco orange recoil spring

Toolcraft BCG

Heavy buffer of my own mfg

Still on order Surefire Procomp 762

 

 

 

 

[unforgiven]

Hell yeah brother 👍

[shooterrex]

Just waiting on a gas tube so I can shoot mine. Shorter flash can and forward assist plug is on order.

[jtallen83]

@willbirdWhere in the cam pin cut out did the 11 1/8 inch gas tube fall? Starting to look like there are at least two different setups on the gas port, my 11 inch falls just a bit past center. Run that thing for a bit before changing anything up, break-in may solve any function issues. 

@shooterrexNice looking rig, gotta love a shorty!

[willbird]

3 hours ago, jtallen83 said:

@willbirdWhere in the cam pin cut out did the 11 1/8 inch gas tube fall? Starting to look like there are at least two different setups on the gas port, my 11 inch falls just a bit past center. Run that thing for a bit before changing anything up, break-in may solve any function issues. 

@shooterrexNice looking rig, gotta love a shorty!

It fell right dead in the middle. The rear of my gas block is 1.125 exactly from the barrel shoulder with the gas hole in gas block centered exactly over the gas port.

Bill

[jtallen83]

1 hour ago, willbird said:

It fell right dead in the middle. The rear of my gas block is 1.125 exactly from the barrel shoulder with the gas hole in gas block centered exactly over the gas port.

Bill

That tells me there are two different configurations then. Is your barrel marked 7.62x51 or 308 Win?

 I have both but forgot to check the spare and can’t remember which one I built off of. Gotta get that on the things to do list for the next trip home.

Edited August 5, 2019 by jtallen83

[willbird]

1 hour ago, jtallen83 said:

That tells me there are two different configurations then. Is your barrel marked 7.62x51 or 308 Win?

 I have both but forgot to check the spare and can’t remember which one I built off of. Gotta get that on the things to do list for the next trip home.

7.62x51

[willbird]

98Z5V turned me onto these buffers....they are not always in stock, if not in stock ask them "notify me" and they will, it gives us a stainless steel body and a 3.5oz buffer as they make it. Good buy at $22

The supplied internals are two steel weights and 2 rubber disks

If we substitute in two tungsten weights from Amazon or Ebay we end up at 5.2oz. I did chuck them in the lathe and use a file to radius the corners, as supplied they had a razor sharp edge. Searching  will lead you to the Ebay seller, they are $23 shipped for 3 of them, "TUNGSTEN WEIGHTS 3 PACK FREE SHIPPING 1.5 OZ"

So we end up with a 5.2 oz buffer for $37.33, and we can mix and match weights to end up with other weights if we desire to. Can also go right to a retailer and buy them for the same price. https://pur-tungsten.com/product/tungsten-recoil-buffer-weights/

This is a buffer I made using the PSA weights that came in my complete PA10 lower, and I made a 1018 steel body and it ended up 5.7oz

Edited August 6, 2019 by willbird

[willbird]

Lots of folks have never been inside a buffer....maybe many folks never will :-). As a kid growing up and as an adult taking things apart to see what is inside is just part of who I am :-).

Bill

[unforgiven]

Nice job on that buffer brother 👍

[willbird]

10 hours ago, unforgiven said:

Nice job on that buffer brother 👍

I give 98Z5 all credit due :-).

Bill

[unforgiven]

You got the hand skills brother 👍 

[willbird]

Surefire Procomp 762 muzzle brake and Brownells BCG showed up today.

Really liking the Procomp, it is honestly the first muzzle brake I have purchased, there will be MANY more for sure. It does add some muzzle blast but makes a huge difference in recoil, this comp was rated near the top as far as $/performance ratio goes.

Really liking how it worked out well with the rail too :-).

[willbird]

Brownells vs toolcraft carriers (folks say TC makes for Brownells) there are some differences, minor ones IMHO

Toolcraft 17.8oz

Brownells 18.4 oz

Brownells is the upper BCG in each picture. The Aero FA does work with the FA notches in the Brownells BCG. When I shop parts I balance the shipped price, time from order to delivery arrival,  with how the vendor takes care of customers, this lets Brownnells win out sometimes with a part that may be a little more expensive.Their packing and shipping is pronto, and they stand behind both their own branded products and other brands of products they sell, just my .02. 

Edited August 7, 2019 by willbird

[willbird]

The slightly heavier carrier is balancing out the slightly lighter buffer IMHO.

Fired a box of Tula 3 rounds at a time and the final 5 and still had a few times it did  not lack back empty.

Will break it in more and evaluate. Really have no desire to burn a lot of Tula in barrels that have proven accurate, but on the other hand it is cheap and avail, and no need to chase the fired brass :-).

Bill

[98Z5V]

I pretty much made up the same thing, bufferwise for my .260 Rem.  I had the DSG bodied buffer weighed at 5.15oz, and another hybrid combo at 5.7oz (for 2.500" buffers). In the .260, sometimes the 5.7 wouldn't lock back - maybe a touch too heavy, I was thinking?  I swapped in the DSG hybrid at the 5.15, and I've never had another problem.

In my case, I know what it is, with that 5.7 buffer - that Wilson Combat .260 barrel had a 0.070" gas port, and I know in my heart that thing needs to be 0.080." That's the difference with those buffers.  That gun comes apart for paint soon, so....   

[willbird]

7 hours ago, 98Z5V said:

I pretty much made up the same thing, bufferwise for my .260 Rem.  I had the DSG bodied buffer weighed at 5.15oz, and another hybrid combo at 5.7oz (for 2.500" buffers). In the .260, sometimes the 5.7 wouldn't lock back - maybe a touch too heavy, I was thinking?  I swapped in the DSG hybrid at the 5.15, and I've never had another problem.

In my case, I know what it is, with that 5.7 buffer - that Wilson Combat .260 barrel had a 0.070" gas port, and I know in my heart that thing needs to be 0.080." That's the difference with those buffers.  That gun comes apart for paint soon, so....   

I want to have White Oak Armament make me some gas tubes before I make any final decisions. I have not had anything back apart to make sure my shortened gas tube is 100%, drilling the cross pin hole in 304 stainless was a %$#& and the end result was not Swiss watch perfect :-).

I need to let the checkbook catch it's breathe a little 😉 but for the final line up I really want one of these gas blocks.

Bill