Recommend me a top notch BCG please

[mdewitt71]

I have a Toolcraft NiB Grendel BCG and a PSA Grendel BCG....
They both work flawlessly and the NiB is the easiest to clean.

[R2BRO]

alright guys, im now kinda pissed off again.

So I went ahead and bought that Toolcraft 6.5G Type II BCG NiB. $106 shipped. Looks shiny and cool and all that, however; once I disassembled its bolt to start checking the Go/NOGO with my MANSON gauges, the GO gauge does not close again...

Some of you might remember, that I initially had ill-machined barrels from BCA, and i had exactly same problem with another regular BCG, the GO gauge did not close. I initiated the return procedure and informed BCA about problem, and they went ahead and sent me a better quality (more expensive 20" straight fluted 6.5G type II) barrel. After that, my old BCG closed with GO gauge, and did not close with NOGO gauge. And precision was really good too.

Later on (500 rounds later), the extractor broke, which resulted me starting this thread.

So now I bought this cool looking Toolcraft BCG, and now the GO gauge does not close with my latest barrel installed (with which previous bolt did close fine but extractor broke later).

So... obvious questions now are:

1. what do I do now? suggestions?

OR.... you think its ok to say *fuckit* and just go ahead and start shooting? even though GO gauge does not close?

(please note: the NOGO gauge does not close either - as required).

ideas?

[R2BRO]

additional note: just measured with calipers it measures around .136, the deepness of that bolt face. so all is good... no idea why its not closing on this bolt but closes on previous (which had later extractor broken - what initiated me to buy new whole BCG of higher quality)

[VASCAR2]

Just to make sure you removed the extractor and ejector from the Toolcraft bolt before attempting to test with go no go gauges. You could also try your BCA bolt with the Toocraft extractor if your Toolcraft bolt still failed gauge test.

I’d measure the BCA bolt and compair all measurements to the Toolcraft bolt to find any differences. Might explain why one bolt passes and one fails.

[A5BLASTER]

I have to ask.

Why didn't you just buy a replacment extractor for your bolt?

With the toolcraft bcg and bolt you just introduced anouther element of a non standard length firing pin, so keep that in mind if you ever go to swapping out parts the toolcraft bolt is cut so it doesn't use a standard length fireing pin.

[R2BRO]

VASCAR2: yes i remove extractor and ejector before measuring, and I only use hands to push it in. so im sure im doing it correctly

A%BLASTER: I did not buy just a replacement exatractor due to the following thought: "if extractor broke like that then its made out of shitty steel, means Bolt is made from same low quality stuff" so I wanted to just replace the whole group.

Ok, now I still have a question: Can I ignore the fact that GO gauge does not close with this toolcraft BCG and go ahead and start firing? Is it ok or is it dangerous? will it create dangerous pressures? Or that happens only if NOGO gauge closes, but if GO gauge doesnt close its not dangerous at all?

(reason for above question is - i might shoot around 100 rounds, and check again the GO gauge and maybe it will close? cuz somewhere on the itnernet forums someone said something like that)

[Klem]

R2BRO,

That 'someone' might have been me recently on another thread.

Yes, you can ignore a GO gauge not closing as long as your ammunition goes into battery. There is talk on the web about a higher potential of slam fire if there's no slop in the chamber of an auto loader but I am sceptical of this as I have never seen or heard about this anywhere else.

The deal with GO/NO GO gauges is they are SAAMI specs however your gun can be a little out of SAAMI and still function fine. For example, my chamber is longer than typical rifle gauges permit yet it functions fine because new brass can stretch a fair bit and from then on I only squeeze it back the minimum .003". As long as your bolt goes into full battery and there's enough space around the neck to release the bullet then you will be fine.

In your case I take it the bolt does not close on the NO-GO? If it doesn't close on a NO-GO then that is normal.

If your gun does not close on both NO-GO and GO gauges then try it with the factory ammunition you want to fire. Factory ammunition and new brass will be typically shorter than the GO gauge. If it fully goes into battery then you are safe and ready to fire with that ammunition.

One point to note...The NO-GO gauge is only an arbitrary length between min and max SAAMI specs. Even if your gun closes on a NO-GO gauge it's not saying the gun is dangerous, just that the headspace is longer than preferred. A third gauge called a FIELD gauge is the max allowable headspace. If it closes on that then DON'T shoot it.

Are you using factory ammunition or reloading your own?

[R2BRO]

how do i know if it fully goes into battery or not?

[Klem]

how do i know if it fully goes into battery or not?

Bolt carrier fully forward. Use bolt-assist if unsure.

[bj139]

Take your upper off your lower, rest the muzzle on the floor and pull the bolt back enough to slip a round in.
Use your thumbs to push the bolt into battery. You can see the bolt lugs turn into battery. Make sure they do.
You should be able to remove the round with the charging handle if your extractor is installed.

[R2BRO]

alright, just tested, and nothing blows up. seems to work fine. need to shoot more and see if it will again break after 500 rounds or not maybe not