Jump to content
308AR.com Community
  • Visit Aero Precision
  • Visit Brownells
  • Visit EuroOptic
  • Visit Site
  • Visit Beachin Tactical
  • Visit Rainier Arms
  • Visit Ballistic Advantage
  • Visit Palmetto State Armory
  • Visit Cabelas
  • Visit Sportsmans Guide

Recommended Posts

Posted

Good idea.  Never thought about getting a UPS account number.  Might make life a bit easier with other things I plan to do in the future. <thumbsup> 

  • Replies 141
  • Created
  • Last Reply

Top Posters In This Topic

Top Posters In This Topic

Posted Images

Posted

Barrel for my carbine upper and gas tube came in today.  I need some headspace gauges, both go and no-go and would also splurge on a field gauge too if one is available for .308 as with the AR15.

 

Got any links or ideas for the gauges?

 

I should have enough parts (and hopefully tools) by this weekend to get started but if not then I can at least do a mock-up but I don't plan on doing even that until I can figure out how to post some good photos on here.

Posted

I got my set from Brownells, about $60 for the Go and No Go gauges.  I passed on the field gauge.

 

I'll check them out today.  Sounds like a great price.

Posted

Gauges ordered.  Got the go and no-go pair from Amazon, right @ $65.00.  Ordered the field gauge from Midway for about $35.00 more.  With this .308 I feel the need to get all 3.

 

Now I got to figure out how to get the camera right.

Posted

While you're so faithfully at it ... Google me a chamber reamer or two just in case my barrel is too tight for the heavier rounds.

 

You're perfectly fine on your own.  Good luck.

Posted

OK, the build is complete and I will hopefully have time to get out to the range this weekend and see if it runs.  With glass and bipod but without ammunition it weighs in at 9.0 lbs.  I decided to try out Leapers new 8x glass, in this case a 2-16x44 30mm unit with locking zero, flip up objective and eye piece covers.  Just fooling with the glass before mounting it is very clear throughout the entire range with no hazing at the edges.  The rings were included.  I will let you all know how it runs.  The only issue seems to be a very stiff bolt catch and a very tight BCG.  The BCG goes into a synthetic oil bath tonight.  I did decide to put a JP adjustable gas block on the barrel and the adjustment screw lines up perfectly with the hole in the rail so I should be able to tune it at the range without having to take the rail off. 

 

 

post-15950-0-81341700-1432931572_thumb.j

post-15950-0-58080300-1432931621_thumb.j

post-15950-0-21291100-1432931655_thumb.j

Posted (edited)

AWESOME ... CONGRATS BOB !!!  <thumbsup>

 

That's one fine looking gun.  Everything looks to have turned out real well.  9 lbs. is what I had targeted for max. weight on mine.  Looks like it's going to have a good balance too.

 

I'm sure the BCG and the bolt catch will ease up in time.  Needs some rounds put through it for break-in.  Think positive.  <thumbsup>

 

I'd like to know how that Leapers scope turns out.  I've had my eye on one for my 7.62x39.

Edited by GRA
Posted

Headspace gauges came in today from Amazon purchase.  Go and No Go.  Field gauge should be in next week from Midway.  It's getting closer.   :))

Posted

OK, big problem.  After soaking the BCG in oil I put everything together to test functions as I got ready to go to the range.  The BCG would not retract into a locked back position but stuck about 70% to 80% of the way back.  It was not back far enough to clear the rear of the magazine and the only way I could release it was to take the buffer tiube off.  As you can see from the picture, there is a mark below the firing pin where the BCG was hanging up on the cocked hammer.

 

I checked my 15 and the hammer doesn't appear to stick up any farther above the rim of the lower than on the 15.  The BCG on the 15; however, has a rather large cutout below the firing pin and is sloped such that it gives far more clearance to allow the BCG to get into the locked back position.  I checked the trigger installation and it appears to be correct (actually I took it out and reinstalled it to ensure it was correct, and it was).

 

Any suggestions? 

 

 

post-15950-0-98432000-1433111110_thumb.j

post-15950-0-39515900-1433111132_thumb.j

Posted

The issue is in the height of this area here, outlined in red.  Want to take a few measurements?  I'll measure a known good BCG for comparison.

 

If it's not that, as the problem, and the BCG measurements come out the same s a known good BCG, then it's in the centerline of the bore in the upper receiver.  That would be a machining issue, and there is nothing you can do about that.

 

Only two things it can be, since you already checked the trigger.

 

Red area below:

 

 

 

 

post-7-0-90970600-1433113225_thumb.jpg

Posted

It is an AIM Surplus BCG.  The area in red is 2 1/4" by 9/32".  I did test operation without the fire control group and it functions normally, although I did not have the buffer tube on and the buffer installed.  I probably should take the hammer out and test it with the tube and buffer in place.

Posted

Just double checked, pulled the hammer and it does pull all the way back.  Now I noticed that the bolt catch, special with the Spike's Tactical, will not engage.  It doesn't seem  to rise enough, but that is another issue (a spring perhaps).  It will begin to catch but will not hold.

Posted

Wasn't really concerned with that pad width or length, but that's interesting - your measurement.

 

You hit a length of 2.25".  I measured mine out (Fulton Armory Chromed BCG) at 2.020".  That means you have a steeper ramp angle, and the Fulton BCG is a shallower ramp angle. Steeper ramp angles are gonna be harder on the hammer pins than shallower ramp angles.

 

I'm more concerned with the height of that pad.  I'll have pics in a few.

 

Here's the pic of the pad length on mine:

 

post-7-0-46727100-1433117393_thumb.jpg

Posted

For the "front" measurement, I went across the flat by the cam pin, and right under the gas key, down to the pad.  I hit a 0.936" for that one.

 

 

post-7-0-76566400-1433117648_thumb.jpg

post-7-0-33090500-1433117661_thumb.jpg

Posted

For the "rear" measurement, I went in front of the forward gas key bolt so I could get on the flat of the gas key, and under to the pad.  I hit 1.190".

 

 

post-7-0-18660900-1433117856_thumb.jpg

post-7-0-17033400-1433117865_thumb.jpg

Posted (edited)

Your dimensions for those measurements have to be higher - thicker.  That's what's binding the carrier on the hammer when you try to cycle it.

 

If your measurements on your carrier are not higher in those areas (not thicker), then your upper has a different centerline bore than what's normal.  It's centerline-bored too low - too close to the lower.  No fixing that.  Just getting a new stripped upper that's machined correctly.

Edited by 98Z5V
Posted

I have a friend that has a 308 build that runs.  The next step is trying my BCG in his build and my trying his in mine.  In the meantime I sent AIM a message with an explanation of what is happening.  While waiting I think I will try to see if I can get the bolt catch working, perhaps try a different spring.

Posted

As soon as I get my barrel nut wrench in this week I'll get started on mine and we'll compare the two.  We both have the same upper receivers and BCG.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...