I just came from the first firing of my new Sig Misquito.
Out of 150 rounds I had 15 failures to fire and one failure for the slide staying back on the last round. Feeding, extraction and ejection were flawless...no problems. The safety is small but it works well. The decocker functions HOWEVER, I was using the decocker to lower the hammer so I could fire a magazine full in double action and it locked the pistol up. The triger would not go back nor the hammer drop. I cleared the pistol and mannually cocked the hammer, reloaded the pistol and normal function resumed.
Having the take down lever just slightly out of position will also lock up the pistol. This lever moves too easy, IMO it should lock up in place.
The single action triger is good while the double action triger is heavy and stacks. I like the sights but I like lots of light on the sides of the front sight.
Accuracy was better that I expected. Keeping 10 shots inside of two inches at 20 yards was not hard to do and this is better than I expect from this type of pistol.
I am disapointed in this pistol. Frankly I expected more from SIG. Sights, accuracy and triger are acceptable but reliability is not. I will try several hundred more rounds to see if it breaks in and becomes reliable. However. this SIG will probably get traded off.

It seems that all the Misquitos are having lots of problems! Looks like the Misquito is just another GSR.

Several people on the SIG fourm report good things after several thousand rounds. But for a .22 costing $359.00 coming from SIG I expected more. Any pistol that has 10% failure to fire and controls that hang up and make the gun inoperable is going to damage the manufactures reputation. I don't think S&Ws Sigma is as bad as this new SIG.

Thanks for the review. You helped save me some money. I was already leaning toward another Ruger and this is all the reinforcement I needed. Sometimes the cheapest is the best.

I have a Mosquito and I can't wait to pass it off some sucker. I'm hoping someone would be dumb enough to give me about $200 for it. Mine jammed, although I can't recall how often because I was distracted by my biggest gripe, the 3000 lb trigger. Even among Mosquitos it's quite heavy.

Spend the extra money and get a Trailside.

Trust your instincts - - they're right on.  The mosquito isn't ready for 'prime time.'  I sent mine to a nationally-known reputable 'smith for some action work because I couldn't stand the 17 lb double-action pull (...that's not a typo - - he measured it at seventeen (17) pounds).  Side note, the SigArms Custom Shop refused to do an 'action job' on it, even at my expense, because it, 'wasn't designed to be worked on,' they said.  Also, I'm still having numerous failures to feed, fire, and extract, even after my 'smith threw in a barrel throat and extractor polishing.  I also have a Trailside, a P-239/.40, and a P-229/.40, all of which I love, so I'm not "Sig Bashing", by any means.  The Mosquito is just NOT "sig quality" and I'm totally surprised they put their name and reputation on it.  Check out other comments on the SIG Forum, but beware of glowing comments on the Mosquito from posters who appear to have some sort of allegience or relationship to SigArms.        

I just knew that Sig wasnt going to put their 100% effort into this weapon.  It was just too good to be true.  Damn, Damn, Damn...

Quoted: I have a Mosquito and I can't wait to pass it off some sucker. I'm hoping someone would be dumb enough to give me about $200 for it. Mine jammed, although I can't recall how often because I was distracted by my biggest gripe, the 3000 lb trigger. Even among Mosquitos it's quite heavy. Spend the extra money and get a Trailside.

After about 500 rnds over two range sessions I think I damaged a nerve in my trigger finger from firing the Mosquito.  So many things wrong with it that I never really got around to accuracy, groups etc.

Mine is back at Sig right now for all the above and a whole lot more.  Sig customer service's best advice was "soak your ammo in oil before you put it in the mag because 22lr ammo is really crap".  Thanks dude that cured everything...

I own Sigs, Glocks, Walthers and a few others - This has got to be the worst pistol I have ever put hands on.

Looks like a Porsche performs like a Yugo.

I also have the new mosquito. Mine has the 3000lb DA trigger pull too. Accuracy was good but feeding was another thing. First time I went out I used federal ammo. Didn't work too good. Switched to the cheap winchester wildcats and it did much better.  Also had trouble with the federal in my SW 22. The federal is copper plated. Maybe that had something to do with it. Has anybody figured out what spring is for what? Recoil spring that is. I think the chamber is on the tight side on these pistols. The manual even suggests oiling the ammo. I'm surprised that the throat  job didn't help.

Quoted: The manual even suggests OILING the AMMO.

NFW.  Dang, what a disapointing bummer.  

This is an update to the orignal post. After putting a total of 500 rounds through this pistol I found no improvement. Failure to fire stayed at about 10% and the controls contuinued to lock up the action. I returned it to the dealer who returned it to Sig. Turn around was only two weeks. Rather than repair the pistol SIG sent a new one. Since it was now a new gun rather than a used one I simply asked for a refund. I am so totally disapointed in the quality of the manufacturing and materials used in this gun that I will not be buying any new SIG products. I own a 226 and 220 and they are outstanding. However. they are older pistols. If the Misquito reflects SIG idea of good quality, design, materials and manufacturing in a new product they are on the decline. I laid out nearly $400.00 for a blow back action 22 LR expecting SIG quality. What I got was an attractively packaged rattle trap with loose tolerances and cheep cast parts and very poor reliability. SIG just lost a fan. Don't get bit by the Misquito.

I was actually thinking about purchasing one. I have owned 4 P228s (still have 2), one P226 and one P239. Those are great guns and I carry one of them every day. However after reading all these and actually handle the Mosquito and experience the extra super heavy DA trigger, it drop off my shopping list immediately. If I want a .22LR plinking pistol I already have my 2004 Olympic limited edition from Ruger; and with the extra heavy DA trigger I might as well buy a Walther P22.

SIG needs to look into this gun befor pissing off a lot more gun owners. I was hoping I can find a reliable gun that closely resemble what I usually use, to save some cost on ammo and practice. It does seem like it's all just a wonderful dream.

The customer service comment to "oil your ammo before you shoot" reminds me of a WWII japanese machine gun that require the same. Wow, what a Great advise. Excuse me, I need to go pick up the ass that I just laughed off.

My Mosquito is still at Sig for "repair".  I think 357Sig did the smart thing and got his money back.  I might do the same thing if the gun is returned with problems (if possible).


I know that Sig knows how to make guns (P226/P220 for example) so there really is NO excuse for a product with this many (or any) problems.

I'm just glad I didn't spend $2500 on a GSR.

CWM4A1; I like "understudy" guns. I own a J frame M34 22 that goes with a M36 and M60 S&Ws, a 4" K frame 22 to go with my M19 S&W, a Colt ACE 22 conversion to go with my Series 70 Colt and a CZ Kadet 22 conversion to go with my CZ 75B, ALL of these "understudy" guns reflect the quality of their centerfire counterparts and are made by the same manufacture as the centerfire mate. The SIG Misquito is woefully outclassed, in every way, by the centerfire SIGs.  Do not expect SIG quality from the Misquito.

357sig: That's a nice collection you got there. I am not a revolver guy, but plan to buy a 686 with 4" barrel for my future home defense need (Fiance/soon to be wife need a reliable gun). I can also buy a 617 for her to practice with.

Most of my collection is auto. Other then the SIG family, I have a CZ75B, 2 BHP (one is 1968 T series in mint condition), Kahr K9, Kimber Custom Eclipse, Ruger MkII 2004 Olympic limited edition, and a Colt Python 6". Time to think about buying the Kadet conversion kit for the CZ75B and the .22LR conversion kit from Kimber for the Custom Eclipse, because those does not get to see daylight very often.

Thanks for letting us know that Mosquito is a trouble gun. From what I can see, much more trouble then the Walther P22. I am Glad that I don't have to fork out $400 (That's the price in PRK) to find this out.