BRN-180M BILLET LOWER RECEIVER Reviews & Ratings

The Brownells BRN-180M® Lower Receiver is specifically designed to pair up with the BRN-180® Upper Receivers to maximize the full potential of this unique line.

While designed to be fully compatible with Mil-Spec lower receiver parts and triggers the BRN-180M® Lower Receiver does away with the traditional receiver extension threads and in their place has a milled in 1913 Picatinny rail section for mounting of Sig Sauer® MCX style stocks.

This Lower Receiver is made from billet 7075 T-6 aluminum with a hard-anodized finish, has integral oversized trigger guard, and the unique features of a threaded bolt catch pin and captive set screw for the takedown pin detent spring, both included.

Due to the proprietary design nature of the BRN-180M® Lower Receiver it will not function with standard AR-15 upper receivers.

See all of our AR15s and AR15 parts here.

View Product

Write a review

Reviews Summary

Customers generally appreciate the BRN-180M billet lower receiver for its solid quality and fit with BRN-180 uppers, with many noting its unique features and ease of assembly. However, some reviewers experienced quality control issues and delays in shipping, leading to a mix of satisfaction and frustration regarding the overall order experience.

What Reviewers Are Saying

Product Quality

68%

Many reviewers highlighted the high quality of the BRN-180M, emphasizing its solid construction, excellent fit and finish, and unique design features that enhance overall performance. Despite some reports of quality control issues, a significant number of users voiced their satisfaction with the machining and durability of the product.

Fit and Compatibility

54%

While most felt that the BRN-180M fits well with BRN-180 uppers, several users reported issues with alignment and fitting parts, particularly concerning the rear takedown pin and detent springs. This inconsistency suggests a need for attention to compatibility with other components.

Installation Challenges

46%

Numerous feedback items mention difficulties during the installation of the lower parts kit, particularly concerning specialized tools and fitting issues. Reviewers suggested that clearer instructions or tools be provided to streamline the building process.

Shipping and Order Experience

32%

A recurring theme among reviews is the delay in shipping; several customers expressed frustration over prolonged processing times before shipment. This delay impacted their overall buying experience, even if they were pleased with the product after receiving it.

Overall Satisfaction

72%

Despite some installation and compatibility concerns, the overall sentiment toward the BRN-180M is positive. Many users expressed a desire to recommend it to others or purchase it again, indicating strong satisfaction with the product's enabling features for custom builds.

Sort by Filter by rating

Good match up to BRN upper

Not real happy with the fact that my order showed 'Processing' for ten days before they finally shipped it. Also ordered the lower receiver parts kit and unlike other reports there was no colored bags indicating what should be installed and when. Not a big deal though. I'm really wondering what was supposed to be different on this lower verses an AR15. Possibly the bolt catch but everything else seemed like a normal AR. Didn't need the A2 grip - used a BCM gunfighter instead. BTW the beaver tail fits fine on the M series lowers. Apparently you can't use a beaver tail grip on the retro version lower. Didnt use the safety as I went with a Radian Ambi safety. Didn't use the trigger and instead went with a Midwest Industries drop in flat-face 3.5lb trigger. The primary difference appeared to be the takedown pin retention springs. I got standard AR springs which were too long on the rear pin as they moved that to a downward orientation and the spring sent was just too long. Ended up cutting about a centimeter of length off. The front takedown spring also seemed too long so about 5mm was cut off on that. No ill effects but recommend putting the cut ends of the springs opposite the detent pins. So I'm unsure if I even needed the lower kit for the BRN 180M. I could have picked the few parts I did needed at my FFL. You may want to double check the Bolt Catch because I'm not certain that's an AR part. It sorta makes sense that it would be different. Haven't gotten it to a range yet but everything fits together well and it all function tests OK. There's a very small amount of detectable play between the upper and lower that the set screw doesn't eliminate but that's just a nitpick. As spec'ed the gun cost just over 1600 with shipping.

For 7 cents, BRN-180M would have 5 stars

The BRN-180M is a great receiver when paired with the BRN-180 upper. Make sure you purchase an ambidextrous safety selector. When folded, my SB Tactical TF1913 brace covers the safety. The BRN-180M would have received 5 stars had Brownells provided a shortened rear takedown pin detent (or spring) with this receiver. The standard AR15 rear detent and spring puts too much pressure on the rear takedown pin which renders it inoperable. In order to assemble/disassemble my firearm for cleaning, I need to take off the grip, loosen the 0.050" hex screw, and pray that it doesn't fly away.

Absolutely buy this. I only have 1 gripe

Milling, fit & finish are perfect. Really nice product. And I would absolutely buy this again. I purchased the lower and brn180s upper. Built many ARs in the last 15 years. I only have 4 stars because 5 would be perfect and the only thing that makes it not perfect is upper to lower fit. Now understand, you generally buy a matched upper lower to achieve 0 play. But I have purchased uppers/lowers not matched and had 0 play. In fairness, Im not sure if this should be addressed to the upper or lower. Brownells is no slouch in this... they put an adjustable tensioning shim where the rear upper receiver pin connects. So you can take out any slight wiggle. But this solution ultimately puts more stress on the takedown pin, and can be an irritation to breakdown rifle if you make it to tight. Again, I would 100% buy this again. But I would have liked to known the above mentioned when I purchased.

Nice Lower

Got this to build a dedicated 22LR AR 15. I am using CMMG barrel, bolt & a Better Mag Adapter. I haven't assembled the lower yet but the fit and finish is very nice. Looking forward to plinking with it soon!