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 top of the line tool
by Bill A
I guess for the price of this piece I was expecting a lot . I was not disappointed. This is a finely crafted and finished tool. That should come in handy for years to come. It's a much better way to do barrel work and upper receiver work than with the prior clamp and poly insert I was using before. Can u do the work without it? Yes. Does this thing allow you to do it like a pro and with ease and less likelyhood of damaging your upper? A most definite yes. Good purchase.
Heavy and Solid
by Rico
Haven't used it yet, but very heavy and solid.
Solid tool
by David
Haven't had a chance to build with it yet, but it's a solid looking tool and I have no doubt it will perform with the quality Geissele is known for.
Review of product and services
by Claude Russell
Great product and service from primaryarms
Geissele Reaction Rod
by Frank
Geissele Reaction Rod from Primary Arms,a must have for your AR builds. A quality piece at a great price, and the shipping was awesome!! Thank you Primary Arms.
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.
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!
Perfect tool for the job
by Luc Rainguet
Excellent tool for this type of job. Tool is a little pricey however
excellent product.
by xm.w
excellent product, excellent service from PrimaryArm also.
Reaction rod
by Bryan
Also have the Magpul block, but this is hands down better in a couple of ways. First it slides into the upper receiver for more support. Secondly I like the fact that you can rotate the upper 360 to work on it. Lastly Primary Arms always gets all of my orders out quickly and is truly two day shipping.