Bolt won't turn into barrel extension.

[Clint]

You guys are basically saying the same thing.

In a properly made barrel, there should be plenty of clearance for the bolt lugs to turn.

This barrel has either a bad extension or bad barrel machining.

Either way it needs to be sent back for a replacement or a refund.

[constructor]

You guys are basically saying the same thing.

In a properly made barrel, there should be plenty of clearance for the bolt lugs to turn.

This barrel has either a bad extension or bad barrel machining.

Either way it needs to be sent back for a replacement or a refund.

Yes I think I said that earlier also, not sure why he wants to argue over .002" and tell me how to measure extensions. He is going off drawings he found on the web and I'm using numbers I programmed the CNCs to and actually measured. ETA- All 4 parts have tolerances including headspace and that changes the stickout of the go gauge/cartridge which changes location of the bolt front within the ext lug to breech area.

[MegademiC]

So lysander says spec is .283-.289"
Constructor was aiming for .287" which is actually on the high side of mid spec. So if constructor is +/- .002" hes withi. Spec. Im assuming lysanders numbers are correct based on history.

So both you guys are in spec. What is OP's bolt lug length!?

[lysander]

The issue is with the limits allowed and customer service.

If the OP calls up the manufacture and says: "Hey, this barrel and extension assembly you sold me has a gap of less than 0.287 inch and my bolts don't fit."

They say, "Well, 0.287" is within spec, so, your bolt must be the problem. Have a nice day!" click.

If the OP call and says, "This barrel and extension assembly you sold me has a gap of less than 0.283 inch and my bolts don't fit." They can't weasel out of correcting the problem.

[bb223]

Update.

Rainier Arms was who I got the barrel from. I contacted their CS who immediately sent a paid shipping label and asked I include my bolt (purchased elsewhere) and I boxed it up and mailed it out.

They emailed me a day after they got it and confirmed it had a bad extension, they did not elaborate what exactly was bad. The issue they mentioned was they could not replace my BCM gas block as they were currently on order and I was given the option to wait until it was in stock, get a refund on the entire order, or get a full refund on the BCM gas block and have them use one of their house ones for free (appears to be Superlative Arms) my only real hang up was the BCM gas block was so well made and snug on the gas block journal as well as being 4140 instead of 416SS, but I figured since the barrel was 416SS anyway using a "lesser" gas block wouldn't be a huge deal and I went with the last option.

Got everything back yesterday and assembled it without issue. Shot it today and so far it's been great and shoots just at 1.5 MOA for 10 rounds with Hornady 55gr FMJ over 25gr Benchmark. Had a few cloverleafs with 24.2 Tac pushing a 69 SMK but they were just preliminary groups that I won't count just yet.

I'm a little ticked it took this long but having everything go together so smoothly (save for that damn forward assist roll pin) and seeing how well it shoots with not much effort makes it all worth it.

[Todd.K]

I slightly close up one end of a roll pin to make them easier to install.

Hold the roll pin down on a hard flat surface and give it a few taps around one end.

[constructor]

The issue is with the limits allowed and customer service.

If the OP calls up the manufacture and says: "Hey, this barrel and extension assembly you sold me has a gap of less than 0.287 inch and my bolts don't fit."

They say, "Well, 0.287" is within spec, so, your bolt must be the problem. Have a nice day!" click.

If the OP call and says, "This barrel and extension assembly you sold me has a gap of less than 0.283 inch and my bolts don't fit." They can't weasel out of correcting the problem.

If the bolt lugs are .277" it will turn in a .283" space. If the bolts lugs are .277" it will not turn in a .276" space. click.

[DwayneZ]

If the bolt lugs are .277" it will turn in a .283" space. If the bolts lugs are .277" it will not turn in a .276" space. click.

Metal can squish 0.001", just need to turn it hard enough.

[DwayneZ]

Update.

Rainier Arms was who I got the barrel from.

Which barrel exactly? RA sells many brands, including their own.
sorry if I missed it in earlier post, I didn't see it mentioned.

[bb223]

Which barrel exactly? RA sells many brands, including their own.
sorry if I missed it in earlier post, I didn't see it mentioned.

Their budget priced house brand barrel. The 16” Select middy with a 5.56 chamber 1/8 twist and medium type profile.