ProgSpear Build thread - AR15 tack driver.

[ProgSpear]

Exactly! We're all just killing time waiting for you to nut up with some hardware porn.....

jeez, tough crowd.... I'll do a dry fit shot later.
The next question for all the guru's is if I'm actually required to get/use the AeroShell 33MS for the barrel and nut, or if the tractor supply red grease I have on hand is ok?

[Meketrefe]

red grease is fine from everything from barrel nuts to sex life.
no much is needed.

[ProgSpear]

for background on this, I decided I needed a new precision hole punch, as the the old one was illegal because it made three holes with every pull of the trigger.

This is dry fit only, but I think it still qualifies as gun porn. 18" .264 LBC/6.5 Grendel upper, Prostaff 3x9-40, Timney 3# trigger. Need to get some gas blocks and it should be complete. I'm being picky and only want clamp on blocks, not the set screw kind. Ultimately I want to upgrade the optics to a FFP mil-dot, but basically this is it.

[DarthVader]

Looks really nice should shoot very nice groups..

Clarence

[Meketrefe]

Yes! that receiver is very nice. Who makes them?
Make sure to give a couple of hundred rounds to break in. The LBC is a tac driver and with plenty of power for large tasks.

[ProgSpear]

Yes! that receiver is very nice. Who makes them?
Make sure to give a couple of hundred rounds to break in. The LBC is a tac driver and with plenty of power for large tasks.

Upper is a no-name Keyhole (Cerro Forge) M4.
Lower is a MAG Tactical Systems that originally came from DSI.

Do you go through the "formal" breakin, or just shoot the pants off them? I've gone through the tedium of doing a shot, clean the bore, repeat, etc. and honestly haven't been able to see any particular difference. I know there's a lot of conflicting dis/mis-information floating about on the web, and I didn't find any specific info on lesbaer.com.

[Meketrefe]

The lower looks nice all beefed up the way I like them.
I don't see any reason to clean after each shot but clean a couple of times the first sessions and go easy on the barrel slowly conditioning the bore.
Always start from a squeaky clean and specially dry bore. People shoot from wet bores sometimes dripping oils and that can cause pressure issues and
even damage a firearm.
There is no one formula nor secret recipe for this, only common sense. So go easy on the barrel and loads at the begining. Groups will start to close up
with a little use. Mine like hornady and lapua loads. Wolf no so much but they are ok for most purposes.
Did you polish the feed ramps? also might wan to run the magazine lips with a stone to remove burrs to make sure they feed smoothly from day one
like if they were already broken in. Depending on the mag I might cut one coil or two off from the spring. Some have too much tension and create
unnecessary frictions both when cycling and feeding. Try them as they are first.

[ProgSpear]

Grrr... No, I didn't polish the ramps. Basically that's just to round the edge between the ramp and chamber so rounds won't "snag" when stripping from the mag, yes? I guess I'm going to get very good at changing barrels. Biggest PITA on this was making sure the gas tube correctly lined up with the bolt key. I found it took very little angular change on the barrel nut for the key to bind.

Also, I still have to pin the "thread protector".

one other Q: Was the headspace checked on this barrel/bolt combo?

[Meketrefe]

Grrr... No, I didn't polish the ramps. Basically that's just to round the edge between the ramp and chamber so rounds won't "snag" when stripping from the mag, yes? I guess I'm going to get very good at changing barrels. Biggest PITA on this was making sure the gas tube correctly lined up with the bolt key. I found it took very little angular change on the barrel nut for the key to bind.

Also, I still have to pin the "thread protector".

one other Q: Was the headspace checked on this barrel/bolt combo?

run it first and see if there is anything biding. sometimes there is no need to polish them. also make sure the hammer doesn't have too much tension. I see this mistake very often in many ARs.
ARP sells the barrels and bolts matched bu in any case and if you do not have a no-go gauge, you can do a quick field check with a casing and scotch tape. It should be a tight chambering that is needed for accuracy. I think the scotch tape puts 2 thousands so you might need to put 2 or 3 cuts to reach no go. Ideally do this with an inert round / dummy produced with your own dies but if you do not have them yet you can use a factory round. Do this w/o the lower, just the upper upside down in the vise. so you can see the cam turning. I temporarily remove the ejector plunger and guide the round into place too past the extractor to make it easier to push into battery and more precise verification. Measure the tape thickness with the calipers so you know the actual difference with no-go.4 to 6 thousands should be perfect but 7-9 is ok too.

[ProgSpear]

OK, everyone gets to vote. Do I need one of these? http://www.midwayusa.com/product/277...age-65-grendel

[Meketrefe]

Once you FL you brass and after trimming it is exactly what you need. If you want to verify a case you can set your caliper to the CASE OAL and use a larger caliber
case to take a delta read from the datum / shoulder of the case. This should match a factory or recent re-sized round withing 1 or 2 thousands.
So the above is a waste of money. At the other hand it is not expensive but I would save that towards a quality trimmer.
The calipers and some pieces of scrap brass and/or rods will tell you everything you need to know about any caliber/casing.

[ProgSpear]

I already have an LE Wilson trimmer, (best that I could afford) so I will need to get the Wilson case holder for 6.5G anyway. just wondered if there was any "value added" in getting the fancy guage.

[Meketrefe]

I already have an LE Wilson trimmer, (best that I could afford) so I will need to get the Wilson case holder for 6.5G anyway. just wondered if there was any "value added" in getting the fancy guage.

It gives a quick check but I don't see the value when one should have gone through all the other steps before anyway. In other words if one follows the proper steps the gauge will always pass
so it is really an unnecessary thing. Perhaps for lazy people who want to take shortcuts when preparing the loads. For pistols the ultimate test is to take the barrel out and do a drop (plunk) test
on the barrel itself.

[ProgSpear]

OK, I have a couple of questions regarding one of the great evil features is defined in unSAFE. The exact text is:

(VI) A FLASH SUPPRESSOR, MUZZLE BREAK, MUZZLE COMPENSATOR, OR THREADED BARREL DESIGNED TO ACCOMMODATE A FLASH SUPPRESSOR, MUZZLE BREAK, OR MUZZLE COMPENSATOR;

My questions pertain to the "OR THREADED BARREL DESIGNED TO ACCOMMODATE" phrase. It's generally assumed that if a "thread protector" is pinned and welded to the barrel that the previously evil barrel has been rendered angelic. First, has that assumption ever been officially acknowledged as valid? Second, a welded pin is considered permanent. Loctite Red 271 is also advertized as being permanent, so why could you not use Loctite Red to make the barrel compliant?

Note that one could grind off a weld retaining a pin just as easily as heating a Loctited barrel to 500 degrees. Also, to prove the lunacy of this law, one could easily put a clamp on "break" on a target barrel, turning it into an evil rage filled terroristic baby killing machine.

EDIT: Hey Meke! I see you did something bad on the "other place".

[WARFAB]

Biggest PITA on this was making sure the gas tube correctly lined up with the bolt key. I found it took very little angular change on the barrel nut for the key to bind.

I think I read a while back that you can insert a gas tube sized drill bit into the carrier key to check barrel nut alignment. Put the barrel nut on and torque until you think it's close, then slide the carrier with the drill bit in it to check alignment.

No idea if it actually works, but that's what I read.