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.

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 :-).

I give 98Z5 all credit due :-). Bill

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

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

7.62x51

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

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

16" no thread sig 400 showed up, looks like it will shorten up nice, has a larger dia where the muzzle will be than my Faxon Pencil does at the end of the 1/2-28. Bill

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

That is exactly what I did with mine to get a rough idea. Need to precisely place the gas block and re do the measurement. I came up with 11-1/8" marking it on the strong side for length. I am going to shorten a gas tube to try and I can take metal off with a lathe but have not mastered putting it back on ;-). Bill

I do know from my own experience that barrel condition can effect pressures. I to have an interest in powder coated cast (or preferably cast, PC, then swaged) bullets in common semi auto calibers. In 350 Legend I was working with a load that seemed modest until I fired more rounds between cleanings, bore condition hanged with round count, and it raised pressures enough to cause visible effects on the fired cases. If we go back into the historical texts of our hobby we will read about cupronickel metal fouling issues that would make a mess of a rifle bore, perhaps something similar could be showing up with what the importers refer to as "bi-metal" bullet jackets ?? If they are not strict about exactly what they are plating onto steel jackets, and how thick it is they could create a metal fouling issue that would differ from rifle to rifle perhaps. The same could be true of drawn jackets as well. The domestic mfg have gotten so good that we take them for granted IMHO. Bill

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

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

OK so I got my Aero M5E1 upper, test fit the shorty barrel, and indeed the Toolcraft bolt locks up just fine with the pin in place. Toolcraft Bolt/Carrier group to be exact.

OK so I got my Aero M5E1 upper, test fit the shorty barrel, and indeed the Toolcraft bolt locks up just fine with the pin in place

A few more pictures here. https://www.osagecountyguns.com/sig-sauer-gasblock-lowpro-m400.html it is a 1/2 oz part.

I was googling on the Sig 400 and found a picture of the gas block...interesting looking part. https://www.sigsauer.com/store/low-profile-gas-block-m400.html

To me "twin" means that if we look at the loading data for a given barrel length, say 20" in this case, the same powder type/charge weight with the same exact bullet gives essentially the same velocity. More or less the difference between a 260 rem and a 6.5 creedmore could be equal to or less than the differences between any two rifles of the same caliber as far as powder type/charge weight and exact same bullet goes. Two "identical" rifles in actual testing (handguns too) have been shown to exhibit as much as 150 fps difference in velocity in calibers like 30-06. Same make and model of remington 700, same barrel length, same ammo, etc.

Build a ladder up to the roof of your compound using Sig 716 barrels as rungs :-). Bill

I was dead set against them because to me they cost so much more. PSA would troll some cheaper complete lowers now and then but the uppers seemed to cost as much as an entire small frame rifle build. BUT they snagged me one day with a complete magpul equipped lower with EPT for like 159 shipped. Once you have one, well they seem to multiply :-). I piled up parts and built a cheap upper for that lower, seems decent :-). Now working on an Aero Sig shorty. Bill

I grabbed one of the sig 400 16" non threaded, that is a steal at $49 shipped IMHO :-). Thinking to chop it down to somewhere between 10.5 and 12.5 to build a 5.56 mini me of the 7.62 sig shorty I'm piling parts up for :-). Bill

PSA has the MOE EPT pistol build kit with SB TACTICAL PDW BRACE on sale for $229. That reeled me in and I grabbed one :-). That brace might be a bit on the heavy side but I like how it looks :-). Hard to exactly compare weight too because the stated weight of some braces does not include a buffer tube and others like the PDW include a proprietary buffer tube in the specified weight. Bill

Just an idea from left field, make sure that the "ejector(s)" will depress if you push on them ?? Not based on any experience of issues with ejectors...just thinking about what could cause it to not go into battery now. Extractor would not have a grip on the case if the ejector was stuck tho. Bill

I have only bought one Faxon but it is very very nice. It is a 16" pencil AR15 barrel, mid gas. Gem like inside and out :-).