Best way to drill a gas port

416stroker · 11-03-2009, 06:21 AM

On a bulgarian 74. I got a kit from apex and now I need to drill the gas port.

I was thinking of picking up another gas block and drilling it all the way threw. So after I set my headspaceing and bolt gap I can just pop on the gas tube and block pin it in place and drill it threw the block and then switch out to the original gas block.

Is there an easier way?

**Winn R** · 11-03-2009, 10:56 AM

There are some blocks that can be used as a drill guide. The '74 blocks are not and are kind of expensive to use sacrificially.

I've found it easier to mill a flat in the top of the barrel and drill it vertically.

Viper Dude · 11-03-2009, 03:58 PM

The small flat on the top of the barrel is helpful for drilling the gas port. I also used a mill with a center drill to start the orfice in the correct spot. This was on my M-40 Tokarev 16.5 inch shorty.

Some AK gas blocks are angled to the barrel and care must be taken not to jam and snap the drill bit. Getting a broken bit out of the gas block and barrel assembly can be a real sonny bee.

VD

**Winn R** · 11-03-2009, 07:18 PM

Another little trick is to start the gas hole with a .25" end mill. That way if the block needs to move a 1/16 or so everything still works.

**sjohnson** · 11-03-2009, 07:45 PM

Like Winn posted, do a 90 and forget the angled port. Much easier to do and the angle doesn't improve function.

416stroker · 11-03-2009, 09:05 PM

Bulgarian ak74s are a 90 degree gas block. I think Ill try what winn posted. Unless I find a gas block that I can use as a guide with out throwing away $30

Edit: I dont have a flat spot on my USD made barrel. So I might just drill one and weld it shut.

**Winn R** · 11-03-2009, 11:03 PM

You have to make your own.

Set the barrel in V blocks, mark the spot and hit it with an end mill. It's so you can get the little .070 bit going.

416stroker · 11-03-2009, 11:06 PM

Ok thanks guys Ill give it a shot. I wish my fist build had original barrels. But this should end up being better.

woodsworld · 11-03-2009, 11:50 PM

I am in the same boat with the APEX 74 kit. Please let me know how you are building the barrel.

416stroker · 11-04-2009, 12:47 AM

Quote:

Originally Posted by woodsworld

I am in the same boat with the APEX 74 kit. Please let me know how you are building the barrel.

I will. Everything esle should be easy. Im just a lill woried about my lack of tools. Im probably going to have to go to my friends machine shop for some of this. But If I do snag up a spare gas block and drill it Your more that welcome to borrow it.