I’ve been jonesing for a suppressor for a couple of years now, but one of the things holding me back was that I didn’t have any suitable hosts. A few weeks ago I was in the LGS and saw this Ruger MkIV Tactical sitting there. I left it there and thought about it for a week, then decided to go back half hoping it would have sold. It hadn’t, so it came home with me.



I’ve had a MkII Stainless Target for a few years now, and it’s been absolutely fantastic...incredibly accurate, great trigger, and more reliable than I ever thought a semi-auto rimfire gun could be. Based on my experience with that, I figured I couldn’t go wrong with a MkIV. I got it home with just a few hours before I had to be at work, so I took it straight to the range without lubing it, which isn’t something I usually do (there was factory lube on it, but I typically will break a new gun down and re-lube it myself before shooting).

That first range session was terrible. 3-4 stovepipes per mag. When it shot it was accurate, but just annoying as all get out clearing jams every few rounds. I was pissed, as I paid more than double what I paid for my MkII for this thing, and that older gun has been superb. Thinking that it may have been a lack of proper lube from the factory, I stripped it down, lubed it, and took it back out, with the same results.

Clearly the gun was having an ejection-related issue as the cases were all clearing the chamber, but not exiting the ejection port. I did some research, and found some stuff about rounds contacting the rear feed lips of the mag prior to reaching the ejector being the cause of the stovepipes.

I compared the mags from my MkII to those that came with my MkIV, and the feed lips are identical. The only difference is that the mag bodies of the MkIV mags have a cutout for the button mag release. I did some dry runs with some empties, and it quickly became apparent that the rounds were indeed hitting the feed lips before the ejector on the MkIV, but not on the MkII.

Turns out the issue lies with the “upgrades” to the MkIV design. The MkII uses a heel mag release that locks the magazine into the gun in a very solid and consistent manner. It’s the same every time, and it doesn’t move at all. The MkIV on the other hand, uses a button mag release and also has a spring-loaded plunger called the “magazine ejector” at the bottom of the grip that loads against the top of the magazine baseplate and launches the magazine out of the gun when the mag release button is pushed. This is another “upgrade” to the design intended to mimic the drop-free functionality of most defensive handgun platforms.





These upgrades at face value seem innocuous, and possibly even desirable as they produce a manual of arms that is familiar to most shooters. However, they were the root of my stovepipe problems. The upgraded magwell of the MkIV is far looser than that of the MkII, and the push-button mag catch doesn’t lock the magazine in as positively as the heel-catch of the MkII does. In addition, the magazine ejector plunger exerts force near the rear of the baseplate, causing the mag to rock back in the magwell under spring pressure and raises the forward part of the deed lips so that extracted rounds can come into contact with it prior to hitting the ejector.



Photo detailing the amount of play in the MkIV magwell when pressing against the mag ejector. The MkII does not exhibit this:


Filing the sharp point off the front of the feed lips and polishing it off allows the extracted rounds to slip over it, properly strike the ejector, and exit the gun as designed. Going too far could cause feed problems by changing the angle in which the rounds in the magazine are presented to the feed ramp, but just taking off the outside corner hits the sweet spot and lets the gun work as it should have from the factory.

Unmodified mag on the left, modified on the right:



Feed lips in relation to the ejector. Unmodified mag at the top, modified mag on the bottom:



The gun came with 2 mags, so I worked one over first and tested it before messing with the other. Using the unmodified mag as a control, I put 150 problem-free rounds through my worked-over magazine, while the unmodified one incurred 3 stovepipes in 10 rounds. I then modified the second mag and put 100+ trouble-free rounds through that one as well. I also polished the follower slides, the follower button, and cleaned any flashing off the followers while I was at it. The gun runs like a top now, and matches my MkII for accuracy (the supplied serrated target sights are awesome!). I just don’t understand why Ruger couldn’t get it right from the factory. I know there are plenty of MkIVs out there that don’t have these problems, so I’m not sure if the issues with my gun are the result of manufacturing tolerances breaking down or something else, but there was clearly a problem and tweaking the feed lips fixed it.

I’ve got a few more things planned for this gun besides the can:

1.) I want to do some chronograph work to see what kind of muzzle velocities I can expect out of the shorter barrel. The internet claims that the barrel is short enough to keep standard velocity .22 ammo from going supersonic, so there’s no need to buy subsonic ammo for optimal suppression out of this gun. We will see if that is true or not.


2.) I already ordered some plug screws from shopruger. As soon as those get here, the hideous rails are coming off. If I do decide to mount a dot at some point, I’ll probably source a low-profile top rail instead of that huge thing that Ruger put on there. I have no use for the lower rail whatsoever.


3.) Volquartsen is basically giving away take-off uppers for these things. I’ve got a 6” target bull-barrel and a stubby pencil-barrel upper on the way to my FFL right now, for less than $100.


4.) The factory trigger isn’t bad, but Volquartsen’s website has a lot of interesting stuff that I could spend money on. I’ll probably run it as-is for a bit just to verify that everything is good to go and set a performance baseline, but I could see swapping out some ignition parts down the road, especially since they get rid of the stupid mag safety.

This message has been edited. Last edited by: 92fstech,

Volquartsen is your friend. Other than the red anodized trigger and thumb safety from Tandemkross, this MK IV Tactical has been upgraded with every available Volquartsen MK IV item. In conjunction with unmodified Ruger OEM mags & CCI 40 gr. standards, the pistol (suppressed) has been 100% reliable. As an added bonus, the Volquartsen kit eliminates the superfluous magazine disconnect safety. Enjoy!

I purchased a Mk IV 22/45 Lite a couple of years ago and it works great. But I made some mods even before firing it, as I have done on past MK IIIs. I first removed the magazine disconnect on the Lite and replaced it with a Volquartsen Blast Shield. I also replaced the extractor with an Exact Edge one. In fact, I also replaced all of the extractors on my 10/22s as well.

So far, no issues with the MK IV or the mags.

I have 2 (not the tactical but MkIV 22/45 lite) and a zillion rounds later neither have hiccuped ever. And a zillion has lots of zeros. I rarely clean them. They don't give a hoot if its suppressed or not (DA Mask if that matters). I can't imagine why yours has issues. I'd have sent it to ruger, but that's just me. People bring these to .22lr matches all the time and they don't misbehave either.

What you are saying describes my MkII perfectly. Utterly reliable over thousands and thousands of rounds.

I'm not sure why this one wasn't right out of the box, but if the fix is as simple as reworking a couple of mags it's not the end of the world. Last time I sent a gun back to Ruger it was a PITA. It was gone for over a month and I got hit with a transfer fee when they ultimately decided to replace it. Then the new gun had the same issue that I'd sent the old one in for, albeit to a lesser degree. If I can avoid going through that again, I will.

quote:

Originally posted by 92fstech:
3.) Volquartsen is basically giving away take-off uppers for these things. I’ve got a 6” target bull-barrel and a stubby pencil-barrel upper on the way to my FFL right now, for less than $100.

I just looked on their website. There are some terrific clearance deals, but they also indicate, "This item must ship to an FFL dealer."

Does this mean the customer has to pay an FFL transfer fee for an upper?

quote:

Originally posted by iron chef:
Does this mean the customer has to pay an FFL transfer fee for an upper?

Yes. Unlike most pistols, the upper is the serialized component of the various Ruger MK series models.

quote:

Originally posted by hjs157:

quote:

Originally posted by iron chef:
Does this mean the customer has to pay an FFL transfer fee for an upper?

Yes. Unlike most pistols, the upper is the serialized component of the various Ruger MK series models.

Yep. Kind of a PITA, but at those prices it's still a good deal. So far Volquartsen has been really easy to deal with, too...nice people and excellent communication. Per UPS it should be getting to my FFL tomorrow.

I'm eyeing the Volquartsen take off barrels. That is a very good price. Did Volquartsen have 6" bull barrels or is it the 5.5" bull barrel?

I think it's the 5.5", but I'll measure it and let you know when I have it in-hand.

My son and I took the MkII and the MkIV out to the range today and burned through 2 325 count boxes of Federal Automatch. We had one stovepipe in each gun, otherwise it was smooth sailing. I had meant to take the chronograph but as we were leaving I realized I'd forgotten all about it. That'll have to wait until next time. We got good use out of the dueling tree, though!

quote:

Originally posted by 92fstech:

Last time I sent a gun back to Ruger it was a PITA. It was gone for over a month and I got hit with a transfer fee when they ultimately decided to replace it.

I bought a new GP-100 revolver that fired the first two rounds, then locked up. Sent it to Ruger, they decided to replace rather than repair. They reimbursed me promptly for the transfer fee.

My SP101 in 22lr did that as well. Good news was they got it back to me pretty quickly.

quote:

Originally posted by SIGfourme:
I'm eyeing the Volquartsen take off barrels. That is a very good price. Did Volquartsen have 6" bull barrels or is it the 5.5" bull barrel?

They came in today, so I broke out the tape measure...the target model has a 5.5" bull barrel.

Bolt, target barrel and thread protector ordered.
Good deal for a Ruger barrel/bolt.

quote:

Originally posted by hjs157:
Volquartsen is your friend...

Yes they are.

At one time they had parts for 17mach2 MarkIII pistols, but not sell a pistol in 17mach2.

The fun part was, if you ordered one of every piece, it would come fully assembled and ready to go.

All standard velocity ammo is subsonic in pistols.

It is actually garden variety high velocity ammo that still mostly stays subsonic in pistol length barrels so while standard velocity ammo is usually needed to keep ammo subsonic in a rifle, it usually isn’t needed in a pistol. Even without going supersonic high velocity ammo will be louder than standard velocity ( subsonic is essentially a fashionable synonym for standard velocity)

Stupid mag safety delete available-->Tandemkross. Blast shield replaces the spring and aligns the magazine.
Free shipping at TandemKross this weekend.
Worth looking at TandemKross for those tune up parts.

quote:

Originally posted by SIGfourme:
Stupid mag safety delete available-->Tandemkross. Blast shield replaces the spring and aligns the magazine.
Free shipping at TandemKross this weekend.
Worth looking at TandemKross for those tune up parts.

Yeah, I saw those. Looks like quality stuff...I'm just trying to decide if I should go that route or just replace everything in there with a complete kit from volquartsen.

Either way, the discretionary part of my next paycheck is going towards the suppressor, and after that I should have about a year to tweak and play with this thing before before the whole package is complete with the can. Nice on the ATF to be so thoughtful and provide me with all that build-out time...

Tandemkross offers a complete kit for Mark 4--Blast Pack--sear, hammer and mag disconnect @ $79.

Waiting on my Volquartsen blem target upper.

My son and I took it out again today and played with all 3 uppers. We went though a full 325 round bulk pack of Federal Automatch. Only had 2 malfunctions...one stovepipe, and one failure to strip a round from the mag (that one may have been user induced...I had him tap and rack and it ran fine for the rest of the mag).



I shot all three upppers over the chronograph....average of 999.5 FPS for the Tactical, 1017.4 FPS for the Target, and 1005.5 FPS for the Standard. So no worries at all about keeping it subsonic.

We took turns shooting some bullseye targets at 15 yards. Nothing to be proud of, but the gun shoots well. The sights on Target upper were about 6" off from the factory and took some adjusting. Thankfully the fixed sights on the Standard (or "Hitler Pistol", as my son calls it) were pretty much dead on.



These were all shot standing unsupported, and I think they speak more to my lack of ability than the capabilities of the gun. I would have thought going into it that the Target upper would have been the easiest to group with, due to the longer sight radius, but I shot it first and and didn't really hit my stride until around targets 7 and 8, and then started to fall off after that.

The bull barrel was no suprise as it handled pretty much like my MKII Target. The Standard was surpisingly light and handy. I almost didn't buy that one, but figured what the heck it was only $35 and I was already ordering the Target. I'm glad I did.

We finished out the day with the 4" plate rack at 15 yards and left the standard uppper on the gun for that. My son kicked my butt right out of the gate with a clean run of all four plates from the low ready at 2.88. The best I could put up was at least a second slower. Between this thing and the MkII, I see us burning up a lot of .22 ammo on the dueling tree this winter.