CMMG AR-15 Lower Springs and Pins KIT - 55AFF75
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CMMG
Overview
The CMMG AR-15 Lower Springs and Pins Kit includes essential components designed to ensure a smooth and reliable operation of your AR-15 platform. This kit is crucial for the proper functioning of the lower receiver, helping to maintain the action of the trigger and hammer while providing stability during firing. This product is commonly found in builds featuring a carbine gas system and chambered in 5.56 NATO, making it a staple for many standard AR-15 configurations.
Specifications
Available Merchants(8)
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Price Alert
October 2026 so far on GunPartPicker
CMMG AR-15 Lower Springs and Pins KIT - 55AFF75 is the fifth most added buffer spring on GunPartPicker so far in October 2026, behind the Geissele Automatics Super 42 Rifle Length Spring, with about 5% of all buffer springs added to builds. That's its 2nd straight month at #5. Builds with this buffer spring are mostly chambered in 5.56 NATO (80%), split between mid-length (51%) and carbine-length (20%) gas systems, and nearly all AR-15.
Availability is good: it was in stock at one retailer or another nearly every day in September 2026, and today 4 of the 8 retailers we track have it in stock. It dipped to $9.78 at KY Gun Company for a stretch in September 2026, well under its usual $12.49, so sales do come around. Buying today, the lowest price is $10.47 at KY Gun Company, above September's low of $9.78, so a better deal may come back.
Updated · from real builds on GunPartPicker · Prices checked · refreshed daily across 37 retailers
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Frequently Built With
The part most often added in each category by the builds that include this one
CMMG AR-15 HD Pivot and Takedown Pin Parts KIT - 55AFF3B
Strike Industries Extended Bolt Catch
Wilson Combat AR-15 Lower Receiver Forged
Rise Armament AR-15 Magazine Release Button - Rise Red
Timber Creek Outdoors Ambidextrous Safety Selector - Black
Rise Armament Advanced Performance Trigger, Red - RA-535-RED-ARP
Build Configuration Breakdown
Aggregated and anonymized data showing how builders use this product
PlatformBased on real build data showing which platform (AR-15, AR-10, AR-9) builders pair with this product.
CaliberBased on real build data showing which calibers builders choose alongside this product.
Gas SystemBased on real build data showing which gas system lengths builders use with this product.
Builds Featuring This Part
See all builds →Builds in the community that include the CMMG AR-15 Lower Springs and Pins Kit - 55AFF75
| Build | Parts | Total |
|---|---|---|
 | 33 | $2778.05 |
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