All around rifle/light build

[phishfood]

I will post pictures, ask component questions, etc.

The general idea is to build a rifle that covers most practical uses pretty well. Truck gun, hunting rifle, target rifle, self defense, range fun gun, the hope is that these tasks can be mostly covered in a single rifle. Also, I am trying to keep it relatively light, with the thought that a lighter rifle is more likely to be carried, and actually be available for whatever purpose it might be needed for.

The first part of this build is a 16" Faxon Gunner barrel. Right now it has a thread protector on it. I have somewhere between 800-1000 rounds through it, and muzzle rise is a minor problem. I shoot a 16" 5.56 a lot, and the difference in muzzle rise/return to target is very noticeable. So I am thinking about a muzzle device. I really don't want to increase muzzle blast at the firing line any more than absolutely necessary, but do want to tame the rise.

I have had it mounted onto an Anderson upper and lower, with Anderson freefloat handguard and trigger. Just today, I took it off of the upper, and lapped a 2A Arms upper without forward assist. I must say that the Anderson upper was very "tight". The lapping tool had to be wiggled and convinced to drop down into it, and would still stand at attention after the lapping tool was oiled and spun extensively. The 2A Arms upper was not nearly so snug. If it weren't for the FA, I would probably have put the barrel back into the Anderson receiver.

[A5BLASTER]

Get the best muzzle brake your money can buy and don't worrie about extra noise on the line. You have to give to get when it comes too brakes. The louder it is the better it works.

Also put adjustable gas on the rifle and a lowmass BCG that will go a long way to help with keeping the muzzle from moving as much.

On the new reciver if the barrel extention is loser fitting. Find you some steel shim stock. It comes in a roll and you can get it in 3 or 5 thousand thickness. Do a heat and freeze compression fit and it will take all the slop out.

Also you need to man up on the rifle a lil more. Grendel is as you see more powerful then that 22 cal poodle shooter.

Hope this helps sir.

[phishfood]

Get the best muzzle brake your money can buy and don't worrie about extra noise on the line. You have to give to get when it comes too brakes. The louder it is the better it works.

Also put adjustable gas on the rifle and a lowmass BCG that will go a long way to help with keeping the muzzle from moving as much.

On the new reciver if the barrel extention is loser fitting. Find you some steel shim stock. It comes in a roll and you can get it in 3 or 5 thousand thickness. Do a heat and freeze compression fit and it will take all the slop out.

Also you need to man up on the rifle a lil more. Grendel is as you see more powerful then that 22 cal poodle shooter.

Hope this helps sir.

Thanks for the help!

I am currently looking on McMaster Carr website at stainless steel shim stock sheets. If I am reading my dial caliper correctly, there is somewhere between 4 and 6 thousandth of play between the barrel extension and the receiver. They have a kit that comes with quite a selection of thicknesses, for about $50. I would probably never need to buy any more shim stock again in my lifetime, but when would I ever use that much shim stock?

[Lastrites]

I put a flash comp on my 16" it helped muzzle rise quite a bit without adding excessive concussion/blast unlike a couple of muzzle brakes I've tried. It's a trade off, like many things in life.

[phishfood]

Well, I went ahead and ordered that selection of stainless shim stock . $50, but I seriously doubt I will ever run out.

As close as I could tell, there was between 5 & 6 thousandth play between the upper and the barrel extension. So I used .003 shim stock. After a bit of trimming to get it the correct length, and to fit around the index pin, it was a very stiff hand push fit for the first 1/8-1/4".

So I very lightly greased the extension, then wrapped the shim stock around it, and greased that, and put it into the freezer. Greased the threads and the inside of the receiver, and put it in the toaster oven at 275. After 45 minutes, they slid together relatively well. Ended up having to use a plastic mallet to finish seating them together. I think the two parts were sharing heat at that point, so the fit got real tight real fast. The biggest PITA was keeping the frost wiped off of the barrel so that there wouldn't be moisture stuck in the mating surface.

I need to find some barrel shims, since the place holder handguard nut I am using for the time being will not time correctly either bare or with the one shim that I currently have.

[Klem]

I need to find some barrel shims, since the place holder handguard nut I am using for the time being will not time correctly either bare or with the one shim that I currently have.

Why don't you file off the tooth that's stopping you from timing a gap wide enough for the gas tube. I've done that before, it works. You don't need every single tooth to torque it up and removing one makes no difference to anything else.

[phishfood]

Why don't you file off the tooth that's stopping you from timing a gap wide enough for the gas tube. I've done that before, it works. You don't need every single tooth to torque it up and removing one makes no difference to anything else.

This particular nut and handguard, the gas tube doesn't pass through the barrel nut. The need for timing is driven by the pattern of the screw holes for the handgaurd. The rail needs to line up with the rail on the receiver, and there are threaded hole around the circumference of the nut that need to line up with the screw holes in the handguard.

Really, my OCD is the only reason this needs to line up. In another couple of weeks, I will be re doing all of this once the handguard I want comes in. I just want to test the accuracy after the receiver has been lapped and the barrel/receiver have been shimmed. So that I can compare it to a test target I shot last weekend before I started taking everything apart.

[Klem]

OK understood.

If you are putting an interim handguard on to test groups then adding spacer shims (to time the handguard) might give a false future accuracy prediction. If you intend replacing the handguard with one that won't require shims then what's the point of testing for accuracy with them?

Heck, why not just screw up the handguard as is? The top rail won't exactly line-up with the upper but you don't need this to test for accuracy (unless using a bipod, and even then if your bipod cants it's a non-issue). If you use bags and rests, and a cantilevered scope mount that does not attach to the handguard then timing the handguard is not necessary.

[Lemonaid]

I have the same situation with needing spacer shims.
I saw these on amazon and will most likely order.
https://www.amazon.com/Float-Barrel-Spac...549&sr=8-1

[Baroid]

I'm very new to firearm building but not new to mechanics, at my job we do percision fitting and shiming one of the things we use to fit and shim very close tolerances pieces is "solid film lubricant" we use it to take up space between the 2 I'm sure theres other uses but that's what we use it for. Spray a lite coat on each, once dyed it's hard as a rock then sand off excess till it barely fits. Also add a little green loctite

[phishfood]

Got home from being out of town this afternoon. Finished putting the rifle back together, and shot some groups.

Went from a rough average of 2 1/2" to 3 3/4". I don't feel I was shooting my best, but I don't think I was that much worse than my normal.

[phishfood]

The Faxon carbon fiber 13" handguard came in yesterday.

I must say, my initial impression is very favorable. Very lightweight, seems very strong.

Hopefully I will be able to get everything put together this weekend.

[gofastman]

I'm planning on switching to a Anderson smooth side upper. I also want to try out a low mass BCG and an FMK polymer lower (4.3oz!) I'm sure this will upset some people, but it's going on a gun for recreational use, so if it sucks it's not a big deal.

[phishfood]

I'm planning on switching to a Anderson smooth side upper. I also want to try out a low mass BCG and an FMK polymer lower (4.3oz!) I'm sure this will upset some people, but it's going on a gun for recreational use, so if it sucks it's not a big deal.

How much does a low mass BCG save you? What does it do to the extraction timing?

And I am sorta with you there, in that I have a New Frontier Armory polymer lower that I am going to put on this rifle. Not to sure if it will stay permanently.

[phishfood]

Put 100 rounds through the sort of finished build last Sunday. Then 50 more today. And the extractor broke. Half of the rim sheared off, obviously causing extraction and ejection problems.

This bolt and extractor have at least 1200 rounds through them, possibly as much as 1400. So I guess that age and metal fatigue could be the culprit. But it does make one wonder when it breaks so soon after a major component change.

Any thoughts?

[VASCAR2]

You lapped the upper so the bolt should be seating in the barrel extension square. Is the barrel over gassed, do you know the diameter of the gas port and are you using an adjustable gas block? The 16 inch Faxon Group Buy barrels had .078 inch gas port set at mid length. Are you using a suppressor and what buffer and spring are you using?

[phishfood]

Using a SLR adjustable block, set to hold the bolt open on empty mag, and brass is dropping at 3:30-4 o'clock.

Didn't think to try and measure the port while I had everything apart.

Gas is mid length.

No suppressor.

I believe that the buffer and spring are standard carbine.

Thanks for taking the time to help.

[VASCAR2]

Sounds like the metal in the extractor might have had a flaw. Massed produced products have a certain percentage of failures. I guess you were unlucky and got a poor quality extractor. In my opinion extractors are like brake pads on a car, they are a wear item and some just last longer than others depending on quality or how hard you use them.

[phishfood]

Kudo post for Faxon.

Contacted them, and they sent out 2 new extractors, postage paid, no charge. Wouldn't even consider taking any money for them.

[phishfood]

Installed a 4-16 Vortex Viper HS in a Burris PEPR mount. Shot it at 50 yards today, printing about 1/2"-5/8" groups at 50 yards.