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U.S. M21 Sniper Rifle (Accurized M14/M1a) | IMI .308 168gr Match

<Transcript> Hey guys, we’re looking at the M21 rifle. Now compared to what the M14 market offers, this particular rifle is far closer to an issued M21 than the current status quo.

So a little back story, The military M21 was an accurized M14 rifle to fulfill a specific role for the U.S. military when they needed a semi auto .30 caliber sniper weapon.

I bought this gem 10 years ago, and it has been a long painful process turning it into an M21. Ten years of agony, countless gunsmiths, and parts purchased.

In 2015, I sent the rifle to my army friend’s father, Ken Corcoran.

Ken earned his President’s 100 tab with an M14, and retired from the Army as a Warrant Officer.

He was on the M21 program, converted and serviced the Army Marksmanship Unit’s M21 rifles. After he left, he was a contractor for Army units to convert their M14 rifles to M21 rifles for deployment.

That’s right. This rifle is put together to the specs of a true military issued M21, by one of the guys who put them together for the AMU.

The Kreiger 1:10 medium weight barrel gives us the accuracy without overloading the already-heavy weapon system.

The weapon was bedded with Bizonite into a McMillan M3a national match stock as the XM25 era M21 rifles were outfitted.

We fitted a GI national match flash hider, with a wider inner diameter for less bullet interference.

The gas system was unitized, and a sadlak tin gas piston was dropped in.

The spring guide was replaced with a national match spring guide to decrease spring binding.

Ken worked on my trigger group to lower the pull to a crisp two-stage 4lbs as the military M21 rifles were issued.

The standard issued Leupold Mk4 scope with M3 turrets were top-line scopes back then… held on with Larue QD rings on a Smith Enterprises M21 mount.

It should be mentioned that the Smith Enterprises mounts actually have an NSN number and “U.S. property” on them, as they were issued.

Here’s the bombshell I’ll drop here. It’s a this rifle is built on a Chinese Polytech M14s.

This was an IDE-stamped Polytech rifle that was forged from 5100 carbon steel, actually tougher than the milspec and springfield armory 8620 steel receivers.

These receivers were reported to be reverse engineered from Vietnam captured M14 rifles, so dimensionally they are as close to the USGI receiver as you can get.

Hate all you want. It’s a good product.

The issue with some chinese M14 rifles is that the bolts may not be properly heat-treated. That’s why I got a USGI TRW bolt to have swapped out.

Alright we’re shooting this with 168 grain IMI Razor core match .308 that was optimized for semi auto weapon systems.

What can I say? You get a gentle shooting rifle with fast follow-up shots.

The McMillan stock is a huge upgrade, and the cheek piece is far superior to the GI 100 mph tape mod.

Again, of the 10 shots, we’re warming the bore with one shot and sending down 9-shot groups.

Don’t forget, the gas port is shoots down and anything that your rifle rests on turns black.

Accuracy? We shot two nine-hole groups, one with a cluster of 0.759 inches and 1.199 inches if you count the flier.

The other was 0.88 inches, however a ceasefire gave me a 30 minute break between the second group and the cold bore shot threw a flier out, 1.528 if you count the cold bore flier.

As an added bonus, I took some of my handloads out and it printed a 0.499 inch 9-hole group, 0.974 inches including the cold bore shot. Not bad for a semi auto.

Prior to the M21 conversion, this was a 2-3MOA rifle. I would determine this rifle to be a 0.8 MOA rifle with factory IMI ammo, and ½ MOA rifle with my handloads.

I will of course post the load data in the description for your information.

Springfield makes an M21 for nearly $3000 with no scope or mounts, $4880 for this scope and mount combo, but it’s a match M1a that has an un-bedded stock with a cheek riser on it, and not a true M21.

The Springfield M25 is closer to my configuration and has an MSRP at a whopping $5278 with no optics, and $7158 with this scope and mount combo.

Looking online for prices, it would cost $4064.39 (excluding gunsmith labor and shipping) to clone the M21 in this video. So really you’re closer to the $5k range.

The M21 is a cool looking rifle with obvious signs that it’s bridged generations of the American serviceman, and it’s even captured attention on the silverscreen.

But if you search the web, you will likely come up with the same few images, and hardly any videos of the rifle in military service.

Parts of the reason is because the sheer amount of M14 EBRs and the Knights M110s started overshadowing the M21 in the mid 2000’s.

In 2004, Facebook just launched, YouTube was still in it’s early stages and this was the newest wonder phone. (Motorolla Razr)

We simply did not have the content sharing infrastructure for PFC Joe Snuffy to spill military intel on youtube.

I love these clone rifles with meaning to them, but on the same day I took my friend’s AR10 and shoot a 0.592 inch 5-shot grouping with the same IMI.

His cost $1,000, scope included. That is 1/5 the price, or 80% cheaper for the same results.

So is it worth it? Ask yourself a few questions:

Do you drive a vehicle like a landrover with loads of hidden costs and potential maintenance issues, but you don’t care, because What Would James Bond do?

Are you patient enough to potentially spend multiple years of your life to make a rifle shoot MOA or watch an entire Nutnfancy video in one sitting?

are you able to go to the range can you fend off unwanted attention like Emma Watson would if she were dropped into a Marine infantry barracks full of lance corporals who just came back from deployment?

If you answer is yes to all of these questions then this is your rifle.

You can build it up slowly from an $800 Polytech, but understand the final price tag that you are looking at before you venture into this project.

If you are looking to get in touch with Mr. Corocan for a genuine U.S. M21 SWS spec rifle, send me an email at and I can put you in touch with him.

Thanks for watching, and we’ll see you next time.

Parts list:

Polytech Rifle $800

Kreiger Medium weight SS 22in barrel 1-10 $524.95

Leupold Mark 4 LR/T 3.5-10x40mm $1099

LaRue 30mm QD Rings $210

OR A.R.M.S. #22 Low rings

Smith Enterprises, M14 scope mount, wire EDM, $275

Sadlak TIN piston $49.53

Harris Bipod 9-13 $98.07

M14 flash hider (nonNM, couldn’t find the NM one) $59.95

McMillan M3a Stock $849.95

Badger Ordnance M14 NM Spring Guide $49.99

USGI leather sling $22.95

USGI TRW bolt $300

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