ATI Omni Stripped Polymer Lower Receiver

69 Review(s)

Availability: TEMPORARILY OUT OF STOCK

Click on image to zoom

Customer Reviews

Items 1 to 10 of 69 total

per page
Page:
  1. 1
  2. 2
  3. 3
  4. 4
  5. 5
  6. ...
  7. 7
Not impressed Review by Ky

I ordered 1 back in March 2013 and picked it up in may when my ffl told me it was in fished my sons build right before Xmas build went together great and put his 22lr conversion kit on it worked great and then he said he wanted to shot 556 we didn't shoot 30rds and it broke now I have a sad little boy lesson learned I'm staying away from polymer lowers for life but not impressed @ all

(Posted on 1/12/2014)

Works great for me Review by Ken

Bought ATI Omni Polymer lower before Thanksgiving last year, arrived at my FFL just after New Town. My 1st build and price was definitely a factor of choice (got the sale price). All parts for the lower build came from PSA and installed without a problem. Did not finish build until Oct '13 due to supply/pricing for Evil Black Rifle parts. I put 70 brass-cased .223 and 5.56 through this build along with an additional 60 steel-cased .223. No problems as of this writing. Everything works as it should. The only thing I noticed, and I have nothing to compare it to, is a small hole between the mag well and the trigger compartment. It appears to be a malformation from the casting process but isn't causing a problem at this time. PSA upr fits snug but no takedown pin problems.

(Posted on 11/23/2013)

<100 rounds and it broke Review by Mark

Half the reason I got this lower was because when I was looking for stripped lowers it was still when they were almost impossible to find. So when I found this one in stock I got it and considered the price reduction to be a bonus. I didn't really think anything about it being polymer and figured it would be fine. Well I was wrong. Built my AR using an 18" bull barrel varmint upper. First time to the range shooting 5.56, I put almost 100 rounds through it, but I don't even think I got up to 100. It broke in the back just bellow where the stock screws in. At first I thought the stock fell off or broke, but upon closer inspection I realized it was actually the lower that broke. So now I'm in the market for a new, absolutely not polymer, lower.

(Posted on 11/13/2013)

Follow-up to my 4/20/13 Review of the ATI Lower Review by John

At the time I wrote my review, My stock was on back-order, so that part of the build had to wait. I later received the stock and found, as noted by several other reviewers, that the buffer retainer hole was too tight. When I pushed the retainer pin in with the spring, it wouldn't pop back up.

I fished it all out, and slightly reamed out the hole, applied some lube, and problem solved!

The rifle is now complete, and I can report that that was the only issue I encountered.

(Posted on 11/7/2013)

ATI stripped lower Review by Morris

Just put the LPK/lower together last night. The first issue was the bolt catch pin was real tough to get in, but I got it. Now the bolt catch is tight and I have to pull it manually to catch the bolt. The second issue is the detent for the rear take pin was like installing a roll pin, I had to drive it in towards the take down pin. Third issue is the Buffer Retainer when push down to screw in the buffer tube, sticks in the down position and has to be pulled up with needle nose. So I think I'll stay away from the polymer lowers from now on.

(Posted on 10/21/2013)

Not Good Review by SW

Bought 2 of the lowers and had problems with the fit of some things but kinda expected that. Did not expect the lower to break in half after having maybe 20 rds shot through it. Cant hardley give them away to anyone now. Buy a forged lower for sure!!!!

(Posted on 10/9/2013)

Here's why you're damaging your ATI Omni lowers, and how to avoid/fix it Review by Scott

First, let me say I've built over 120 AR lowers in the last two years alone for various folks, and while I prefer metal lowers there is really nothing wrong with the ATI Omni lower if you're familiar with building ARs. Many who have damaged their lowers by splitting the bolt catch pin mount haven't understood why this happened even after doing the damage, so I'm trying to help those who are about to build one, or if you read the entire "review", would like to fix their broken lower.

The main problem with the OMNI polymer lower lies in the fact that the bolt catch used on a typical AR lower rely on a roll pin for the pivot of the catch itself. The roll pin diameter is typically .093", which will be reduced in diameter when installed in a forged lower. This will occur due to the force put on the pin; since it is a split pin, the use of a punch to drive it into the lower and through the catch will compress the pin, reducing its diameter enough so that the pin is small enough to allow the catch to freely move.

The problem with the ATI Omni is that rather then the pin closing up when driven into the lower, it is as likely to split the part of the lower that you're driving it into. The polymer isn't strong enough at that location to compress the pin; that is why you're finding that you bolt catch won't move freely, or that your bolt doesn't release or doesn't stay locked, depending on the position you catch is stuck in. If you got this far without splitting the hole the pin is driven into, congratulations, now you get to remove the pin and do it right.

The solution is very easy, but must be done before driving the pin into the lower, and there are actually a few things you can do.

Compress the pin's diameter if using the pin from your LPK; to do this simply use a pliers (a "Channel Lock" may give you more leverage) completely. Your pin will then start out smaller in diameter, and will fit much easier into the hole, and with a bit of gun grease or oil can be driven much easier than before, with less likelihood of splitting the catch area.

Another option is simply to purchase a smaller diameter pin to begin with. Your local hardware store will likely have the next size down (.800" long and .093" - 3/32" is the original, and the next one down is usually 5/64" - .078). The smaller pin is usually fine, but I still lube them before installation.

A third option is to slightly enlarge the hole in the polymer. I do not recommend this as it exacerbates the weakness of the bolt catch pin mount - which is in part the problem to begin with. Since any hardware store worth its salt will have roll pins, go for a different option. If you choose to enlarge the hole - DO NOT USE A POWER TOOL TO DO SO! Do this by hand so you can do it slowly; doing it quickly will cause more problems than you need.

Now - if you do split one of the lower bolt catch pin mounts, all is not lost. A marvelous product called JB Weld exists, and is the answer. JB Weld is an expoxy, and works very well in this situation; make sure the area is clean and oil-free - REALLY oil-free or the epoxy won't work. JB Weld is available in most hardware stores, and even Wal-Mart carries it. You can find out more here: http://www.jbweld.com/products/surface-applications/plastic-composite-pvc/

I have repaired two OMNI lowers that were presented to me by soon-to-be customers, and the repairs I did on them are still holding up today. While I have a nice plastic welding system in my shop, most won't have that equipment, so I won't cover that here.

Good luck and good building!

(Posted on 9/8/2013)

NEWER ONES ARE BETTER. Review by PRISONGUARD1

I HAD ORDERED TWO PRIOR TO DECEMBER '12. THEY FIT SNUG WITH NO WOBBLE. ONE I SOLD OTHER I STILL USE. I PRDERED 4 MORE AFTER THE FIRST OF THE YEAR. THEY WERE ALL WAY TOO TIGHT. I DID CRACK ONE AT THE REAR TAKE-DOWN. I DID FIGURE A WAY TO DE-STRESS THE TAKE DOWN HOLE WHICH MADE THEM SERVICEABLE. I CRACKED ANOTHER WHEN INSTALLING BOLT CATCH (MY FAULT). TWO I SENT BACK WITH AN RRA PROVIDED BY ATI. THEY OFFERED TO COMPLETE THE NEW LOWER FOR $100, CAME OUT TO $96 AND CHANGE. I DID HAVE TO SEND THEM THROUGH MY FFL, SINCE I WAS DOING PAPER ON A 'ROCK RIVER' NO COST. THE NEW ONES SEEM TO FIT SNUG ON VARIOUS UPPERS I HAVE.

THEY ALSO HAVE A REINFORCED AREA AT THE REAR TAKE DOWN. WHICH SHOULD ELIMINATE CRACKING.

(Posted on 7/31/2013)

Issue with takedown pin Review by Andrew

I ordered three ATI polymer lowers due to my own rush to find some stripped lowers. I didn't look to see that the lowers were polymer and just hit the order button.

I installed a standard LPK on the first of the three lowers with relatively little issue. When I took a 16" CMMG upper that fits an RRA and Bushmaster lower with no issue the takedown pin WOULD NOT get past the lug. I then proceeded to try the 20" upper from the Bushmaster that fits the RRA lower...no dice with the ATI lower. Upon closer inspection I could tell that the pin wasn't going to make it through the hole in either upper and could see marks on both lugs where I attempted to ram the pin home. My guess is that the hole wasn't bored in the proper location on the Omni lower.

I now get to figure out how to rectify this issue which will probably include me having to remove all of the parts from the lower and send it back to either ATI or PSA.

Anybody in Houston,TX, want to buy two ATI Omni lowers FTF? :)

I think I'll stick with forged lowers for the forseeable future.

Buyer beware...

(Posted on 7/9/2013)

Learned my lesson Review by Charles

Bought two of these on a whim thinking maybe I'd build a couple of dedicated 22LRs off them. Neither one survived the process of installing the LPKs. I realize that others have managed to build them out into functional firearms, and that's great for them, but this was FAR from my first time assembling a stripped lower and as far as I'm concerned if it's so fragile that it breaks when installing the bolt catch roll pin it's also too fragile to be anywhere near my face when a round is fired.

This was my first and last experience with polymer lowers. I'm not going to trust anything less than a forged receiver again.

(Posted on 5/19/2013)

Items 1 to 10 of 69 total

per page
Page:
  1. 1
  2. 2
  3. 3
  4. 4
  5. 5
  6. ...
  7. 7

Write Your Own Review

Only registered users can write reviews. Please, log in or register