Albroswift

Yea, trying to be clear, OP buying parts didn't want him to end up with a 4" buffer, but then again it would be a start for a 9mm build, I've started with less...

Not wrong. Vltor A5 length = Armalite AR10 Carbine extension length, 7 11/16 +/- internal. Correct on H3. Any H3, 29.00 same as 69.00 one. Can't use Voltr A5 buffer, too long. I found a source for the tungsten buffer weights for around $4.20 each, save $$ re-weighting lighter buffers.

Don't think so. Last build I went with the Sons of liberty 9 position tube, really like it, rifle spring (EA1095 or Sprinco Red). 5.4 oz +/- H3 buffer. Got the tube from Rooftop Defense https://www.rooftopdefense.com/product/sons-of-liberty-gun-works-a5-receiver-extension-buffer-tube-9-position/ Primary has them also. https://www.primaryarms.com/sons-of-liberty-gun-works-loyal-9-a5-buffer-tube-9-position https://www.primaryarms.com/expo-arms-h3-ar15-carbine-buffer-od-green

You would think, but you would be incorrect...

Rule #63 If no one responds you need to buy one and report back! Welcome to the forum.

That's good! @Dewey Mack makes some good points, I may have been backwards on the ejection pattern but would swear that more pressure brings my rounds back. Also agree about the gas tube location and the bolt firing pin hole. Brother was having cratering problems/ pierced primers/ stuck pin due to primer debris, gave him a dual ejector SRC high pressure I had extra really made a difference. This is what the gas tube should look like.

AWM are good mags. I don't have problems with other mags either usually run the C-Products stainless steel, fits the budget and 100% reliable.

1:00 ejection I would drill up one or 2 more sizes, pretty sure it takes more gas to go from 1:00 to 3:00-4:00. To answer your question, I like the Seekins Precision but there are a lot of good ones. An AGB won't help until you are gassed correctly/ little over.

Those are just fine, always have a couple spares laying around. I also just radius the square ones and polish.

I am surprised the firing pin is so much smaller then the hole. You have the correct 0.065 firing pin, I don't have a HP bolt laying around to measure but 0.083 sounds like the bolt for a standard pressure pin. Big hole will cause problems. What do the primers look like after firing?

One thing about the less expensive bits, the shank is undersized compared to the hole called out or drilled, so once you find a snug fit you need to measure with the digital or dial caliper. Then order quality bits next sizes up. my bet you will end up running wit a 48, 47, or 2mm. If you are patient you could start small and test each size.

I like the cobalt as well, stay sharp longer, but maybe just a little more brittle. Just go easy. Some barrels have a hard outer coating as well as the bore. you can slide a wood dowel in the barrel if you prefer for punch through. I have bought Maxtool, Uxcell, topline cobalt's off amazon all good. I have a mill so it is real easy, but most of the brothers here use a cordless drill with success.

Have you shot it with current configuration? The 0.077 would be close, I used the numbered bit that equates to 0.079 (don't remember which one that is) on 3 different .308's, one with Carbine Gas / 18" barrel and the other 2 with 12-1/2" barrels and different custom length gas tubes. All 3 have AGB's but run close to all the way open. Ran one with 7" buffer tube and short buffer / tailhook tube. Orange spring. Another option would be to get a numbered set of bits, and sneak up on the correct size with a fixed AGB, more range trips but eliminate the AGB. I would also get an orange sprinco spring if it was me running the short buffer.

Vortex was good about replacing a crossfire for me. It is their entry level line, and is easier to damage apparently. on mine the culprit was over tightened rings. Bought used.

I've done a couple 40's, brothers have done a 40 and a 45, now a 10. Thinking 10mm is about on the edge for blowbacks without delay.

Haven't shot it yet, maybe next weekend. CMC PCC FCGRadian Talon short throw ambiStern Defense BCGSprinco red springNFA 16" barrel and NFA receiver set w/ LRBHOSightmark M Spec circle dot RDSMFT minimalist stockJT Pistol gripPaired a 7-11/16" SOLGW 9 position buffer tube with an extra long 5 tungsten weight buffer. Length with the BCG came out about 1/8" behind the bolt catch, about right no quarters. Maybe get out to the range next weekend see if it actually works. May need some tuning of the buffer and spring. Should be close. Cerakote Graphite black over gold

Limited experience, but had to drill up a 308 and a 6.5 Creedmore BA. Post the port diameter when the barrel shows up. Numbered drill bit set is ideal for determining size of port. I would expect around 0.079 would run about right with your setup, lots of experts here so might get some other advice on that. Also watch for gas tubes, 12-1/16" (Large frame carbine) is usually correct, 11-3/4" (ar15 midlength) usually a little short. But not always. Both the 6.5 and the 308 BA's I messed with took 12-1/16" Gas tube should hit center of cam cut out. This is a 12-1/16 in an Anderson AM10 Carbine. Just right. Came with a 11-3/4"

Actually Ramen

No ramen, but quick shipping and 7-11/16" +/- internal depth extension.

I have the old Dillon RT1200 power head trimmer for the 650, flies through them but they need a little case lube on them. Die is almost as tight as a sizing die, maybe to prevent chatter. Set up for 308, 223, 338, 44. Can run sizing/ deprime operation in the first station at the same time. Don't like using the case feeder with the imperial wax on the larger cases, picks up dirt, but the one shot works on the 223 in the feeder.

Ramen is OK.

Hey, All Anyone done any business with Rooftop Defense? https://www.rooftopdefense.com/ Need a 7-11/16 extension, they have them and will ship to WA, where as no one else with them in stock will. I gotta get outa this place... Thanks-- Al

Some good pointers.

Hunting partner's truck.

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