Details
Details
The Geissele Reaction Rod® (5.56/.223) is an essential AR-15 maintenance tool engineered for precision and durability. Perfect for gunsmiths and DIY enthusiasts, this tool simplifies the installation and removal of barrels, flash hiders, gas blocks, and handguards without risking damage to your upper receiver. Unlike traditional receiver vise blocks, the Reaction Rod transfers torque directly to the barrel extension, bypassing delicate components like the receiver index pin. Machined from a solid bar of 4140 Chrome Moly steel, it’s heat-treated, tempered, and ground to an exact diameter for a secure, wobble-free fit. Compatible with standard AR-15 and HK MR556 uppers, the Reaction Rod is proudly made in the USA at Geissele Automatics’ state-of-the-art facility in North Wales, PA—delivering unmatched strength, performance, and protection for your rifle.
Features:
- Designed specifically for 5.56/.223 AR-15 upper receivers
- Made from 4140 Chrome Moly steel for maximum strength
- Quenched, tempered, and precision-ground for flawless fit
- Prevents marring and distortion of receiver components
- Enables secure vertical or horizontal vise mounting
- Compatible with AR-15 and HK MR556 uppers
- Manufactured in the USA by Geissele Automatics
- Geissele Tools
California Prop 65 warning
WARNING: This product can expose you to chemicals, which are known to the State of California to cause Cancer and Reproductive Harm. For more information go to www.P65Warnings.ca.gov.Ratings & Reviews
43 reviews
A must have for AR builders.
by MARK -
Where has this tool been all my life? I have built many AR's using nothing more than a bench vice, receiver blocks, and a G.I. barrel wrench. Dear god, after using this tool I was amazed at how easy building an upper could be. Using this tool made an agonizing and sometimes bloody job of replacing barrels and muzzle devices effortless. It is the usual Geisselle quality and is more than worth the price. Going to get the AR10 model as soon as I need it.
Wish I'd have had this years ago
by BradZ -
faster than the action blocks, doesn't mar the finish, you can put the upper at any angle you'd like. Breaks the barrel nut much smoother. I needed something for my HK MR556 so I gave this a shot, great tool.
Amazing Tool
by Squib308 -
fantastic tool. why did I wait so long to acquire this. well worth the expense.
CUSTOM BUILD
by GREG
I have done a few builds with a vise block and this reaction rod will make your life so much easier. It will not put pressure on your upper. Every bit helps accuracy.
Need more information........
by Michael
""WON'T FIT
by Charles Mackenzie
It won't fit into the barrel extension even after a scary amount of effort. I was afraid I'd ruin my barrel extension. I was very disappointed.""
Charles, you need to do more than this, you need to return it and tell us what they said, Even Rolls Royce's get returned from time to time with a problem. Another reason is safety, If you have a problem with your upper wouldn't you like to know about it before you have a dangerous malfunction. I dont work for Giessele but Ive bought triggers from them and found them to be an excellent company eager to fix anything that is truly wrong with their products. Call em up. Then get back to us, we'd all like to hear what the problem was. Michael
Expensive, but works very well
by - -
Works beautifully for torquing barrel nuts and muzzle devices. If you're going to be assembling gas blocks, consider getting Geissele's "Armorer's Package" that includes their gas block tools as well.
Superb!
by Scott Reid
Expensive? Yes. Quality? Definitely!Much better option than using any other upper receiver type clamp. It fits snug, feels rock solid when attaching a barrel or compensator. Very happy with this purchase!
reaction rod
by Neil Laljie
It's a little shorter than expected but other than that it was just as described shipped and delivered very quickly will definitely order from them again
Geissele rod
by Fernando Cordova
a must have for a smooth ar build.Fast shipping :)
geissele reaction rod for ar-15 uppers
by willis lancaster
fit in upper is great, clamps in vise well.holds upper very tight, just have to keep upper pushed toward rod.worked great in 7.62x39 upper as well as 5.56/223, and 300 blackout.