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AR-15 MBA-3/MBA-4 Carbine Castle Nut Black Steel
AR-15 MBA-3/MBA-4 Carbine Castle Nut Black Steel
AR-15 MBA-3/MBA-4 Carbine Castle Nut Black Steel
AR-15 MBA-3/MBA-4 Carbine Castle Nut Black Steel
None
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LUTH-AR LLC - AR-15 MBA-3/MBA-4 Carbine Castle Nut Black Steel

4 Reviews
AR-15 MBA-3/MBA-4 Carbine Castle Nut Black Steel
Brownells #
100028004
MFR #
CS-02
UPC
859819007201
$5.19
Coupon Code
Purchase Limit Help

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International purchase information

Specifications
Item Weight (lbs):
0.300
Make Model Fit:
AR-15.Universal;AR-308.Universal
Color:
Black
Item Height (Inches):
0.375
Item Length (Inches):
1.350
Item Width (Inches):
1.350
Material:
Steel
Restriction
Gun Part Restrictions:
Yes
View US State Restrictions
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International purchase information

What is the LUTH-AR LLC - AR-15 MBA-3/MBA-4 Carbine Castle Nut Black Steel?

FITS: The Luth-AR Carbine Lock Ring/Castle Nut for MBA-3 and MBA-4 Carbine Buffer Kits, as well as any Mil-Spec or Commercial Carbine receiver extension.

See all of our AR15s and AR15 parts here.

Gun Part Restriction
Gun Parts have restricted shipping to CA.

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AR-15 MBA-3/MBA-4 CARBINE CASTLE NUT REVIEWS

4.3
4 Reviews
5 Stars
50%
4 Stars
25%
3 Stars
25%
2 Stars
0%
1 Stars
0%
5
Nice!
This castle nut worked great. Tightened to 40 ft/lbs and everything is strait and tight. The groves for staking are nice and deep, which allow for strong staking. Don’t be concerned with the low price, this item good to go.
Would you recommend this? Yes, I would recommend to a friend
by Chris on May 29, 2025
Verified Purchase
Was this review helpful? 0
5
Great quality for little $
For the price I decided to purchase this as an emergency backup part. But the quality was so nice I decided to use it on my build. It's a nice part for a very little investment
by CHARLES MCCONNELL on January 10, 2024
Verified Purchase
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4
good value
looks to be well made. threads are slightly loose on mil-spec receiver extensions. Tried it on Aero, Bravo co. and Brownells extensions with same result. Works ok.
by Bushytale on September 10, 2020
Was this review helpful? 1
3
A bit loose.
Not the best finish but acceptable. The main issue is the nut sits just a bit loose on a BCM buffer tube rather than a snug fit--there is a little wobble back and forth between threads. I give it 3 stars for dirt-cheap pricing.
by AH on August 23, 2023
Verified Purchase
Was this review helpful? 1
Customer Questions
0 Questions