I have a outback I finally got apart to clean, but saw they have a new mono core. Is it worth it?

Details please.. I have an outback that is 12 years old... can you upgrade without a new stamp?

Well worth doing; you're replacing the core, not the outer can which is serialized, so no new stamp is needed.

I had it done to mine and now it is capable of being used on all rimfire except the .17 Super Mag.

First round pop with a .17 Mach II was a bit loud, but much quieter on subsequent shots with that round and .22 LR.

Gemtech IOU Program

Probably the best $249 I've spent from the gun budget in recent years, turned a 2006 paperweight (basically full of lead/carbon) into my current favorite rimfire can.  It is silly quiet and allows me to use it on my SMG and my 22 WMR.  Win, win, win.  I posted a long winded response to the same question from someone else, I've copied it below.  

I had an original sealed Outback 2 purchased in late 2006 (took possession January 2007) as my first silencer. I loved that thing with thousands and thousands of rounds. I didn't really keep track exactly how much went through it but it was, conservatively, north of 6,000 rounds (~80% rifle). It was never cleaned using any sort of soak. Around 2010 it became sufficiently loud that I stopped using it entirely so it sat in a box in my safe. My AAC Prodigy effectively became my only rimfire can for several years. I missed out on the original upgrade program they offered where you could pick your own baffle material, glad I did as this latest upgrade turned out better IMHO. As soon as the IOU program was offered I jumped on board because of all the new capabilities it conferred, most importantly the ability to service it by the owner. The IOU upgrade also permitted me to use it on my then go-to rifle, a ruger 77/22 mag, and my M11/9 SMG w/ Lage 22 kit.

My IOU upgraded Outback 2 sounds great on everything I've used it on so far, Ruger 10/22, Walther P22, and various rimfire ARs including a belt-fed Razorback. I can hardly describe how much fun it is to shoot steel plates at 200 yd with a suppressed belt-fed 22 and iron sights I may be less sensitive to FRP than others, but when shooting my IOU OB2 against my brother's Spectre 2 on P22s back to back, I could not tell much difference. Neither could my brother or the third party observer listening from 10 yd away w/o knowledge of which was being fired when. Of my hosts so far, the 22 mag bolt gun is probably the most impressive to me. Out in the open, the combination is silly quiet compared to what I am used to the 22 mag sounding like. Again, it sounds excellent on everything I've tried and is just stupid lightweight. Taking it apart is super easy, but I always loosen and re-tighten the core after shooting due to experience with my AAC Prodigy. Also, once you clue in to the fact that servicing the core doesn't mean it needs to be spotless, cleaning is easy too. I pull out the core, knock it a few times on the work bench, brush out the bigger crap, brush out the tube, add a dab of grease to the internal threads, and reassemble. Also, I would like to buy a beer for whoever it was at Gemtech that decided to integrate the 1/4" drive feature into the IOU/GM22 core. For me, the $249 allowed me to transform what had become a government regulated paperweight back into a star performing multi-role user-serviceable silencer. I have had zero problems with the core loosening from the tube which I read another user had experienced. I have absolutely no complaints about this upgrade, if I had 10 more OB2s I would have upgraded them all and not batted an eye after seeing how effective it was.  I believe someone from Gemtech also mentioned that, at that time (late 2014/ early 2015) the IOU core going into the upgrades was slightly quieter than the GM22. I may have to look for that post but I am 95% certain. That is also great

There is one model for which it is pointless and a downgrade.

I own a Gemtech Outback II T . It is of all titanium construction. While heavier than aluminum, it is lighter than steel. It is tough and durable. The Outback is famous for minimal first round pop, and this one is the same. To me it is easier to clean... well. I prefer it to my SilencerCo Sparrow. I use the Sparrow on dark guns and the Outback II T on stainless guns.

Other than that specific model, it is a great upgrade.




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exactly my problem. I got my outback apart and cleaned it, but its needs a new core IMO.

Love my Gm-22 (Outback upgrade core) it does have some FRP on pistol only unless you add a touch of grease/water/oil then FRP goes away. If Gemtech would make a limited run of titanium construction GM-22 (natural TI  grey finish) I would be ordering one or two for sure. I've shot my GM-22 with a touch of oil inside and for a magazine (10rds)  it's quieter than any other rimfire suppressor I own same pistol host. Basically once the FRP is gone dry or fired Wet the GM is one quiet dude.

 I really consider my GM-22 a "Wet" can its so easy to charge being monocore and slides apart in seconds. I shoot it wet on rifle alot it's stupid quiet on bolt gun.  I don't think the GM-22 is the best "One rimfire suppressor " or high volume shooting model but for a guy looking for a second or third suppressor I think it's a sleeper most people way under  estimate. Heck I way under estimated  it myself it's been a pleasant surprise in my gear bag.

I need to find my old post, but I also used the Gemtech IOU upgrade.  Mine was an old AAC Pilot however.  Pretty much the same backstory as above.  Had it since '04 and lord knows how many rounds I put through it.  P22, 10/22, AR 22lr kit, all kinds of stuff.  Well, mine wasn't full but it was pretty bad.

After checking with Gemtech to make sure it was compatible I shipped it off in December of 14.  Got it back in January and boy was I impressed!  My only other 22lr can in my possession at that time was also a Prodigy (well, a Prodigy II that had cleared in Nov '14) so now I was up to two monocore serviceable cans.  After the upgrade it does have more FRP than it originally did as a sealed "K" baffle can (and Dr. Dater said it would as the Pilot is longer than an Outback so it has a bigger blast chamber) but after that first pop it's just as quiet as my Prodigy or my Sparrow.  I think the Element II still wins.  I was very happy as said before to take a stamped paperweight and turn it into a modern user serviceable silencer.

Also, I pretty much clean mine the same way.  Take the core out, knock the crud off, little brushing and back in it goes.  Same thing I do with my Mist and Prodigy.  I'd do the upgrade again in a heartbeat.

I did it a couple years ago.  Saw the gemtec rep at the phx SAR show.  Got the details from him, gave him the can the next day.  Took a few weeks.

I just wish they would of buffed the scratches out tho...