Skip to content


This is a caliber exchange kit for the P226 RX pistol.



9mm Luger


Switch it up with a caliber exchange kit for your SIG SAUER P226 RX. This caliber exchange kit includes a complete upper receiver with a barrel chambered in 9mm. Ideal for switching between ammunition supplies or simply converting for personal preference. Caliber exchange kits offer a great way for P226 pistol users to bring modularity to their SIG pistol.

Note: CALX kit comes with contrast sights.
CALIBER X-CHANGE KIT, P226, 9mm, RX, BLK is rated 4.4 out of 5 by 17.
Rated 5 out of 5 by from Highly Recommended, Excellent Engineering. I am a NRA Certified Firearms Instructor and purchased the P226, TAC-OPS conversion kit for its Romeo1 sight. I am big fan of the red dot sighting system for my students that have any vision issues related to sight and target clarity. (ie... age, eye damage) The Romeo1 allows rapid target acquisition and fire control. Two critical skills needed in any defensive situation. The Romeo1 sight is ideal on a concealed carry firearm. (My favorite carry firearm is the P320 RX Compact with its Romeo1 sight.) I used the 9mm conversion kit to convert one of my P226 40 S&W pistol into a 9mm pistol for training. (The performance compares with the Legion series of P226.)
Date published: 2018-10-09
Rated 4 out of 5 by from Great addition a little pricey I have a 9mm P226 EE but wanted to add a Reflex sight. I wish you could purchase only a milled slide or the slide and optic to keep the cost down. I didn't need the barrel, magazine or recoil spring assembly. I'm 100% satisfied with the function and quality of both the slide and the Romeo 1. The cost prevented me from giving it 5 stars. Sending the slide off to get milled and purchasing a Romeo1 would save you about $100.
Date published: 2018-09-12
Rated 4 out of 5 by from 9mm Barrel with Romeo Optic I recently purchased this barrel with optic and very pleased with it. The only drawback is the iron sights are higher than traditional which allows you to use them with the optic but it might not fit into your holster. I have a couple of the hard holsters and with one (no retention LVL1) I trimmed back the plastic to accommodate the optic and it fit fine with the other (LVL2) it wouldn't fit due to front optic.
Date published: 2018-09-13
Rated 5 out of 5 by from Easy and Accurate Being almost 70 and starting to have vision issues, I was finding it harder to hit my normal pistol target (a 7 3/4 inch Shoot-N-C) with 100% accuracy. After purchasing a new slide with the Romeo 1 sight attached I had no problem staying inside the target at 20 yards the first time I used it. Accurate and easy to Use. What more can you ask for?
Date published: 2019-01-08
Rated 3 out of 5 by from Why not threaded barrel It arrived and the right leaf of the front sight was out of the slide. I went through the RMA process it was a couple weeks which delayed my intended use as I paid for 2 day shipping. But they did jix the issue and returned it. Now I know why they use suppressor height sights but you'd think they'd offer this item with a threaded barrel.
Date published: 2018-12-07
Rated 1 out of 5 by from 226 rx 9mm I bought a little while ago and am very pleased with the product. I shot a couple of matches with this setup right out of the box and I am impressed with it. Takes a little getting used to using a red dot on a pistol for me but overall I recommend it. For a factory product with no modification it is well worth it if you shoot alot
Date published: 2018-09-12
Rated 2 out of 5 by from Three disappointments I bought this caliber x-change kit directly from Sig Sauer for my 25 year old, barely used P226. The main reason is for the integrated Romeo 1 site and it's accompanied iron sites. My first disappointment was noticing that the rear iron site was scratched when installed. My second disappointment was how sloppy this new slide fits on my barely used frame. It has twice the side play as the original slide. My third disappointment was when I called customer service, the rep initially indicated the slide play may need to be "fitted" and that he would check with his people and get back to me. I didn't hear anything in a week so I called back. The rep I talked to this time said the loose fit isn't a problem but happening because of the different manufacturing processes used back 25 years ago and now. Not sue I agree, anyway I then mentioned the rear iron site and he offered to fix that. I would have to send the slide back and I thought that would be too wasteful so I declined.
Date published: 2018-09-12
Rated 5 out of 5 by from Great setup! When my change kit arrived I converted my P226 over to the new setup. Fit and feel were just like I anticipated for Sig. Took it to the range and, with minor adjustments, had both the iron sights and Romeo aligned on target. Never a fear now of loosing my red dot without backup. Well worth it.
Date published: 2018-09-13
  • y_2019, m_2, d_16, h_19
  • bvseo_bulk, prod_bvrr, vn_bulk_2.0.11
  • cp_1, bvpage1
  • co_hasreviews, tv_0, tr_17
  • loc_en_US, sid_CALX-226-9-B-RX, prod, sort_[SortEntry(order=RELEVANCE, direction=DESCENDING)]
  • clientName_sigsauer
  • bvseo_sdk, p_sdk, 3.2.1
  • CLOUD, getContent, 100.84ms
  • bvseo_sdk, p_sdk, 3.2.1
  • CLOUD, getContent, 64.04ms
  • bvseo-msg: HTTP status code of 404 was returned;

Please Enter Your Zipcode

Some states have legal restrictions for the purchase of items so we need to ask for your location.

Get Updates

[gravityform id=1 title=false description=false tabindex=0]