Rifle Parts
Whether you're building a new rifle from scratch or looking to upgrade an existing firearm, our vast selection of rifle parts has everything you are going to need in that journey. At Rainier Arms' selection of rifle parts, you can find a wide variety of products including lower and upper parts, trigger parts, muzzle devices, and many more.
Explore our selection of high-quality parts coming from various leading manufacturers like Strike Industries, Magpul, BCM, and many more.
Also, don't forget to check our specially-made Rainier Arms barrels for your firearms.
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Fortis MFG AR-15 REV 2.0 Free Float Rail System - Black★ ReviewsPopup content startsclose Popup
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from real shoppers4.8 star rating 30224 Reviews- Site Reviews
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Thank you for posting a review!We value your input. Share your review so everyone else can enjoy it too.Thank you for posting a review!Your review was sent successfully and is now waiting for our staff to publish it.Verified Reviewer0.0 star rating02/25/25PPatrick G.Verified Buyer5.0 star rating02/24/25Another great Combo valueReview by Patrick G. on 24 Feb 2025 review stating Another great Combo valueRainer mag combos are unbeatable!On Hera Arms H3T Polymer Magazine - 30 Round OD Green (5 Pack)PPatrick G.Verified Buyer5.0 star rating02/24/25Exceptional ValueReview by Patrick G. on 24 Feb 2025 review stating Exceptional ValueRainer magazine combo deals have been great! Get you some.On Elite Tactical Systems (ETS) CZ Scorpion Evo 9mm Magazine - 30rd (10 PACK)GGilbert S.Verified Buyer5.0 star rating02/23/25PWS MK1 lowerReview by Gilbert S. on 23 Feb 2025 review stating PWS MK1 lowerIt’s my first PWS lower and I can’t say to much great things about it. Best lower receiver for the price.On Primary Weapons Systems MK1 MOD 2-M AR-15 Stripped Ambidextrous Lower ReceiverGGage R.Verified Buyer4.0 star rating02/23/25Decent upgradeReview by Gage R. on 23 Feb 2025 review stating Decent upgradeOverall feel and look is great. Pay attention to the description about magazine compatibility. Also I had to due some minor sanding to get proper fitmentOn Mirzon Sig Sauer P320 Enhanced Grip Module Gen 2PPatrick M.Verified Buyer5.0 star rating02/23/25Sharps LowerReview by Patrick M. on 23 Feb 2025 review stating Sharps LowerAmazing quality and craftsmanshipOn Sharps Bros Showdown AR-15 Lower Receiver$132.95 - $189.95 -
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Barrel Length
- 3.1" 1 item
- 4" 5 items
- 4.5" 2 items
- 5" 3 items
- 5.5" 8 items
- 6" 6 items
- 6.5" 2 items
- 6.75" 1 item
- 7" 3 items
- 7.5" 9 items
- 7.75" 2 items
- 8" 8 items
- 8.3" 2 items
- 8.5" 6 items
- 8.75" 1 item
- 9" 1 item
- 9.75" 1 item
- 10" 1 item
- 10.3" 15 items
- 10.5" 28 items
- 10.7" 3 items
- 11.5" 11 items
- 12" 6 items
- 12.3" 1 item
- 12.5" 15 items
- 13" 2 items
- 13.5" 1 item
- 13.7" 3 items
- 13.9" 4 items
- 14.5" 26 items
- 16" 78 items
- 16.1" 3 items
- 16.25" 1 item
- 16.3" 1 item
- 18" 46 items
- 20" 16 items
- 20.5" 1 item
- 22" 14 items
- 24" 6 items
- 26" 4 items
Caliber
- .22 ARC 2 items
- .22 Cal 1 item
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- .223/5.56 17 items
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- .223 Wylde 34 items
- .30 Cal 4 items
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- .308 Win 30 items
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- 300 Blackout 29 items
- 300 Norma Mag 1 item
- 338 Lapua 2 items
- 350 Legend 2 items
- 5.56X45 5 items
- 5.56 NATO 100 items
- 5.56mm 8 items
- 6mm ARC 14 items
- 6.5 Creedmoor 25 items
- 6.5 Grendel 13 items
- 6.5 PRC 2 items
- 6.8 SPC 2 items
- 6MM Creedmoor 5 items
- 7.62mm 5 items
- 7.62x39 7 items
- 7.62x51 6 items
- 8.6 Blackout 9 items
- 9mm 54 items
Category
Configuration
- 90 Degree 1 item
- AR-10 2 items
- AR-15 17 items
- Clamp on Piston Block 1 item
- Cross 1 item
- Curved 15 items
- Flaming Pig 1 item
- Flat 16 items
- Gen 1-3 1 item
- Gen 3 2 items
- GEN 2 1 item
- Ghetto Blaster 1 item
- M-LOK 7 items
- M4 Curve 1 item
- Mil-Spec 1 item
- Normal CQR 2 items
- Restricted CQR 2 items
- Rifle 2 items
- Right Hand 1 item
- Solid Piston Block 1 item
- Straight 7 items
- .625 DIA 5 items
- .750 DIA 4 items
- .800 DIA 2 items
- .875 DIA 3 items
- .936 DIA 3 items
- Standard Buffer and Spring 1 item
- Enhanced Finger Placement (EFP) 1 item
- Type 1 Trunnion 1 item
- Type 2 Trunnion 1 item
- AK74 [WL 5.62"/143mm][HD .32"/8mm] 1 item
- AIMS-74 [WL 4.80"/122mm][HD .32"/8mm] 1 item
- AK-105 JBI Custom [WL 4.20"/107mm][HD .45"/11mm] 1 item
- AKM Large Bore [WL 5.83"/148mm][HD .31"/8mm] 1 item
- AMD65 [WL 4.67"/119mm][HD .31"/8mm] 1 item
- Arsenal Rifle Small Bore [WL 5.75"/146mm][HD .30"/8mm] 1 item
- Arsenal Rifle Large Bore [WL 5.75"/146mm][HD .30"/8mm] 1 item
- 5.45 Krinkov [WL 2.03"/52mm][HD .32"/8mm] 1 item
- 7.62 Krinkov [WL 2.22"/56mm][HD .31"/8mm] 1 item
- Bulgarian 5.45 Krinkov [WL 2.03"/52mm][HD .42"/11mm] 1 item
- Bulgarian AK74 [WL 5.62"/143mm][HD .42"/11mm] 1 item
- DRACO [WL 4.78"/121mm][HD .32"/8mm] 1 item
- Galil Ace [WL 2.15"/118mm][HD .32"/8mm] 1 item
- M85 [WL 4.41"/112mm][HD .31"/8mm] 1 item
- M92 2.218 [WL 3.90"/99mm][HD .30"/8mm] 1 item
- PSL [WL 3.90"/99mm][HD .30"/8mm] 1 item
- Valmet M76 / Galil Classic ARM [WL 4.20"/107mm][HD .45"/11mm] 1 item
- VEPR Small Bore [WL 5.62"/143mm][HD .32"/8mm] 1 item
- VEPR Big Bore [WL 5.62"/143mm][HD .32"/8mm] 1 item
- WZ89 Onyks [WL 2.15"/55mm][HD .32"/8mm] 1 item
Finish
- Bead Blast Stainless Steel 1 item
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- Carbon Fiber 7 items
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- Grey 1 item
- Melonite 1 item
- NiB-X 3 items
- Nickel Boron 2 items
- Nitride 86 items
- Nitromet 4 items
- Phosphate 5 items
- Polished 29 items
- Red 1 item
- Satin 56 items
- Anodize 43 items
- PVD/CVD 1 item
- Quench Polish Quench (QPQ) 4 items
Gas System Length
Inside Diameter
Manufacturer
- 21st Tec 6 items
- A3 Tactical 29 items
- Accu-Tac 1 item
- Advanced Armament Company (AAC) 3 items
- Aero Precision 5 items
- Aeroknox 2 items
- Airborne Arms 3 items
- ALG Defense 5 items
- American Trigger Company (ATC) 3 items
- Andro Corp Industries 5 items
- Angstadt Arms 8 items
- Apex Tactical Specialties 4 items
- Arisaka 6 items
- Armaspec 4 items
- Arms Republic 6 items
- Ascalon Arms 6 items
- Brügger & Thomet (B&T) 1 item
- B5 Systems 18 items
- Ballistic Advantage 20 items
- Battle Arms Development 7 items
- Blackout Defense 1 item
- Black River MFG 1 item
- Blitzkrieg Components 13 items
- BOBRO 1 item
- Bootleg 2 items
- Boss Barrels 12 items
- Bravo Company MFG (BCM) 50 items
- Brigand Arms 2 items
- Centurion Arms 23 items
- Chisel Machining 5 items
- Christensen Arms 3 items
- CMC Triggers 1 item
- Cross Machine Tool (CMT) 6 items
- CZ-USA 1 item
- Daniel Defense 21 items
- Dead Air Armament 4 items
- Dead Foot Arms LLC 5 items
- Devil Dog Concepts 7 items
- Die Free Co 3 items
- DPM Systems Technologies 2 items
- Drew Meyers Defense 6 items
- Driven Arms Co. 14 items
- Eartune 1 item
- Elftmann Tactical 3 items
- Emissary Development 8 items
- F-1 Firearms 3 items
- F5 MFG 3 items
- Faxon Firearms 34 items
- Fightlite Industries 1 item
- Form Rifle 11 items
- Fortis MFG 43 items
- Forward Controls Design 85 items
- FosTecH 1 item
- Gear Head Works 4 items
- Geissele 27 items
- Grand Power 2 items
- Grey Birch MFG 1 item
- Grey Ghost Precision 1 item
- Griffin Armament 14 items
- Half Cocked Arms (HCA) 1 item
- HB Industries 5 items
- HERA ARMS 8 items
- Heresy Design 7 items
- Hiperfire 13 items
- HUXWRX 5 items
- Icarus Precision 2 items
- Icon Defense 4 items
- Jacob Grey 1 item
- James Madison Tactical (JMT) 3 items
- JK Armament 5 items
- JL Billet 5 items
- JMAC Customs 63 items
- JMK Customs 17 items
- JP Enterprises Inc 34 items
- KAK Industries 1 item
- Killer Innovations 1 item
- Kinetic Development Group 3 items
- Knight’s Armament Company (KAC) 4 items
- KNS Precision 14 items
- Kaw Valley Precision 2 items
- Kratos Design Group 1 item
- Krebs Customs 6 items
- KynSHOT 4 items
- Lantac 10 items
- Law Tactical 2 items
- Lewis Machine & Tool (LMT) 21 items
- Mad Pig 4 items
- Magpul Industries 57 items
- Matador Arms 1 item
- Maxim Defense 24 items
- MCM Firearms 1 item
- Mega Arms 1 item
- Midwest Industries 19 items
- Mission First Tactical 1 item
- Multitasker Tools 1 item
- NEMO Arms 3 items
- Neverwear Springs 1 item
- Next Level Armament 16 items
- NIGHT FISION 1 item
- Noveske 33 items
- Obsidian Arms 1 item
- Odin Works 1 item
- Patriot Ordnance Factory (POF) 6 items
- Precision Armament 9 items
- Precision Reflex Inc 2 items
- Primary Weapon Systems 11 items
- Q, LLC 17 items
- Quarter Circle 10 7 items
- R&D Precision 2 items
- Radian Weapons 19 items
- Rainier Arms, LLC 172 items
- Rainier Industries 15 items
- Rehv Arms 1 item
- Reptilia Corp 8 items
- Rex Silentium 1 item
- Riflespeed 3 items
- Rise Armament 18 items
- ROAM Rifles 4 items
- RogueOps 5 items
- RS Regulate 4 items
- Samson Manufacturing Corp. 1 item
- SB Tactical 10 items
- SCALARWORKS 1 item
- Seekins Precision 1 item
- Sharps Bros 19 items
- Shooting Innovations 2 items
- Sig Sauer 6 items
- Silencerco 1 item
- Sionics Weapon Systems 1 item
- SLR Rifleworks 2 items
- Sons of Liberty Gun Works 34 items
- Spinta Precision 2 items
- Sprinco (Tactical Springs) 7 items
- Stag Arms 1 item
- Stern Defense 7 items
- Strike Industries 15 items
- Superlative Arms 14 items
- Surefire 5 items
- Tactical Edge Arms 2 items
- Tango Down 1 item
- Timney Triggers 29 items
- Tippmann Arms 1 item
- Torrent Suppressors 1 item
- Triggertech 5 items
- TruCalibre 3 items
- True North Concepts 9 items
- True Precision 3 items
- Tyrant Designs 11 items
- Underground Tactical 1 item
- Unity Tactical 1 item
- V Seven Weapon Systems 37 items
- VLTOR 8 items
- White Label Armory 1 item
- WMD Guns 8 items
- WOOX 4 items
Model
Option
- AK-47/74 9 items
- AR-9 4 items
- AR-10 24 items
- AR-15 149 items
- Standard 6 items
- 4.720" 2 items
- 6.295" 2 items
- 7.870" 2 items
- 9.445" 2 items
- H2 Buffer 2 items
- White - Standard Power 1 item
- Blue - Enhanced Power 1 item
- Red - Extra Power 1 item
- Orange - Extra Extra Power 1 item
- Yellow - Reduced Power 1 item
- White/Red - Intermediate Power 1 item
- Green - Rifle Length Standard Power 1 item
- Remington 700 Short Action 1 item
- Remington 700 Short Action BDL 1 item
- WA 1 item
- KS 1 item
- JP Silent Captured Spring - Standard 1 item
- JP Silent Captured Spring - Heavy 1 item
- JP Silent Captured Spring - 9mm 1 item
- Buffer & Spring - Standard 3 items
- Buffer & Spring - 9mm 2 items
- Buffer & Spring - H1 3 items
- Buffer & Spring - H2 2 items
- Buffer & Spring - H3 2 items
- Heavy 1 item
- CZ 12 items
- FNH 1 item
- Heckler & Koch 1 item
- Remington 1 item
- Sharps Bros 1 item
- Sig Sauer 2 items
- Springfield 1 item
- Holed 1 item
- Profile 1 item
- Small Lever 2 items
- Large Lever 1 item
- Green Laser 2 items
- Adjustable 11 items
- Non-Adjustable 15 items
- Dimpled 3 items
- Serrated 4 items
- 9.5" 2 items
- 11" 2 items
- Polymer 1 item
- Aluminum 1 item
- Smooth 6 items
- Grid 2 items
- Honeycomb 4 items
- Honeycomb w/ Logo 1 item
- Textured 3 items
- Skelestock 2 items
- Xeno 1 item
- Triangle Stock 2 items
- Modular 1 item
- Traditional 7 items
- Tactical 7 items
- Folding 7 items
- +10 4 items
- With Handstop 4 items
Platform
Price
Product Type
- 10/22 Barrel 1 item
- 10/22 Receiver 3 items
- Accessory 3 items
- Adapter Plate 2 items
- AK Accessories 1 item
- AK Handguard 1 item
- Angled Grip 19 items
- Anti Walk Pins 3 items
- AR-10/LR308 Barrel 47 items
- AR-10 / LR 308 Charging Handle 7 items
- AR-10 Complete Lower Receiver 1 item
- AR-10 Complete Upper Receiver 1 item
- AR-10 Partial Upper Receiver 2 items
- AR-10 Handguard 1 item
- AR-10 Receiver Set 3 items
- AR-10 Stripped Lower Receiver 1 item
- AR-10 Stripped Upper Receiver 1 item
- AR-15 Assembled Upper Receiver 4 items
- AR-15 Barrel 166 items
- AR-15 Charging Handle 29 items
- AR-15 Complete Lower Receiver 11 items
- AR-15 Complete Upper Receiver 33 items
- AR-15 Partial Upper Receiver 20 items
- AR-15 Handguard 63 items
- AR-15 Receiver Set 10 items
- AR-15 Rifle 1 item
- AR-15 Stripped Lower Receiver 27 items
- AR-15 Stripped Upper Receiver 13 items
- AR-9 Complete Lower Receiver 1 item
- AR-9 Partial Upper Receiver 1 item
- AR-9 Receiver Set 2 items
- AR-9 Upper Receiver 5 items
- Barrel Adapter 2 items
- Barrel Nut 4 items
- Blast Shield 1 item
- Bolt 15 items
- Bolt-Action Barrel 29 items
- Bolt Carrier Group 27 items
- Bolt Catch 14 items
- Brace 25 items
- Buffer 24 items
- Buffer Kit 8 items
- Buffer Spring 15 items
- Buffer Tube 9 items
- Builders Kit 1 item
- Buttpad 1 item
- Cam Pin 4 items
- Castle Nut 4 items
- Castle Nut / End Plate 5 items
- Cable Clip 1 item
- Charging Handle 31 items
- Chassis 28 items
- Cheek Riser 5 items
- Compensator 38 items
- Complete Upper 8 items
- Crush Washer 3 items
- Dust Cover 12 items
- End Cap 4 items
- End Plate 12 items
- Failure Resistant Extractor 2 items
- Finger Stop 2 items
- Firing Pin 6 items
- Flash Hider 47 items
- Forearm Accesory 18 items
- Forward Assist 6 items
- Forward Assist Spring 1 item
- Front Sight 2 items
- Gas Block 31 items
- Gas Rings 3 items
- Gas Tube 4 items
- Grip Accessory 10 items
- Grip Module 1 item
- Grip Screw 1 item
- Handguard 44 items
- Handguard Adaptor 2 items
- Handstop 42 items
- Iron Sight 1 item
- Lower Parts Kit 11 items
- Magazine 1 item
- Magazine Button 2 items
- Magazine Catch 8 items
- Magazine Release 13 items
- Magazine Spring 1 item
- Magwell 3 items
- Muzzle Brake 62 items
- Muzzle Device Accessory 12 items
- Partial Upper Receiver 1 item
- Parts Kit 13 items
- Pistol Grip 58 items
- Piston 1 item
- Piston System 6 items
- Port Door 4 items
- Port Door Rod 4 items
- Port Door Spring 1 item
- Rail Adapter 8 items
- Rail Cover 2 items
- Rail Panel 12 items
- Rail Section 1 item
- Recoil Spring 1 item
- Retainer Pin 4 items
- Roll Pin 1 item
- Safety Selector 29 items
- Shim Set 2 items
- Sight Post 10 items
- Silent Captured Spring 2 items
- Sling Mount 1 item
- Spring 8 items
- Steyr Aug Barrel 4 items
- Stock 71 items
- Stock Accessory 16 items
- Stock Adapter 23 items
- Suppressor Accessory 1 item
- Take Down / Pivot Pins 16 items
- Trigger 90 items
- Trigger / Hammer Pins 4 items
- Trigger Guard 13 items
- Upper Parts Kit 2 items
- Vertical Grip 29 items
- Weight 1 item
Rail Length
- 3.25" 1 item
- 4" 2 items
- 4.25" 4 items
- 4.5" 2 items
- 4.9" 1 item
- 5.5" 1 item
- 5.99" 1 item
- 6.0" 4 items
- 6.25" 2 items
- 6.375" 1 item
- 6.5" 1 item
- 6.7" 6 items
- 6.75" 3 items
- 7" 9 items
- 7.2" 1 item
- 7.25" 1 item
- 7.3" 1 item
- 7.5" 2 items
- 7.8" 1 item
- 7.9" 1 item
- 8" 4 items
- 8.5" 2 items
- 8.6" 1 item
- 9" 6 items
- 9.1" 1 item
- 9.15" 1 item
- 9.2" 2 items
- 9.25" 1 item
- 9.3" 3 items
- 9.5" 16 items
- 9.55" 6 items
- 9.59" 1 item
- 9.6" 6 items
- 9.75" 3 items
- 10" 15 items
- 10.5" 12 items
- 10.64" 1 item
- 10.7" 3 items
- 10.75" 3 items
- 11" 3 items
- 11.1" 2 items
- 11.25" 1 item
- 11.5" 8 items
- 11.7" 3 items
- 11.75" 2 items
- 11.8" 4 items
- 12" 19 items
- 12.25" 1 item
- 12.3" 1 item
- 12.4" 3 items
- 12.43" 1 item
- 12.5" 10 items
- 12.55" 1 item
- 12.6" 3 items
- 12.75" 1 item
- 12.8" 1 item
- 13" 11 items
- 13.25" 2 items
- 13.5" 10 items
- 13.6" 3 items
- 13.625" 1 item
- 13.7" 4 items
- 13.75" 1 item
- 13.8" 6 items
- 14" 7 items
- 14.3" 1 item
- 15" 29 items
- 15.25" 1 item
- 15.3" 7 items
- 15.5" 2 items
- 16.3" 1 item
- 16.5" 3 items
Size
Thread Pitch
Twist Rate
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