[Andyd]

I shot two HK4s and both were ammo sensitive. Obviously they did better with High Velocity ammo but so far I have not found out on which ammo they run reliably and with the current ammo crisis, I am a little restricted on rimfire ammo brands. When the gun runs, it is a nice shooter! I like it a little better even than the rimfire Walther PP - and those are long time favorites of mine.

So, who has found that .22 LR round that makes this sweet little pistol shoot without malfunction?

 

[SkippySanchez]

Not familiar with that particular model but FWIW, CCI Mini-Mag is considered the gold standard for reliable semi-auto use.

Now, good luck finding some.

I'd give my right arm to be ambidextrous.

 

[Andyd]

I have fired four different loads through it. Geco semi auto, Aguila SV, Remington Thunderbolts and Winchester Wildcats. While I still have several other other brands, CCI Mini Mags among them, I was looking for a short cut.

I know that many small rimfire pistols and rimfire conversions can be finicky but I hate to waste my time and ammunition to solve this problem.

 

[SkippySanchez]

I have fired four different loads through it. Geco semi auto, Aguila SV, Remington Thunderbolts and Winchester Wildcats. While I still have several other other brands, CCI Mini Mags among them, I was looking for a short cut.

I know that many small rimfire pistols and rimfire conversions can be finicky but I hate to waste my time and ammunition to solve this problem.

I sure understand. My only rimfire pistols at present are Walthers, a PPK/S 22 and a P22, though I have had others, including a 1911 .22 conversation. And yes, 22s can be picky.

My 22s don't get out much but I have noticed they behave much better if the rails, guide rods and barrels are freshly oiled before I shoot.

I'd give my right arm to be ambidextrous.

 

[Bib]

Take a round and see if it drops into the chamber and seats itself. If it does then invert the weapon and see if it freely falls out. If the round does not chamber by itself with only gravity helping or does not fall out of invert weapon only by gravity helping, the chamber is dirty and needs a vigorous cleaning. Emphasis on vigorous. If the round freely seats itself and freely falls out, take some of the rounds you were using when you had the malfunctions and see if some ten or so freely drop in and fall out. If you find some rounds drop in and out and others do not, 22 ammo is notorious for being manufactured with liberal specifications. Scrub the chamber regardless - 22 ammo carbon ring in the chamber area is a fact of life with rimfire.

 

[Andyd]

Bib,

I had chambering problems with Aguila SV in one of my Hammerli Internationals, while it seated fine in all other Hammerlis that I tried it in. Aguila also needs an extra push to fit in the Korth cylinder.

The problem I had was with ejection. The empties were often stuck inside the ejection port and some did not feed but got hung up. I will check the gun out again and see if I find the problem. I am suspecting a little bit that it has to do with the slide and ejector being a one size fits all for .22, .25, .32 and .380.

 

[Bib]

For whatever it is worth - the spring and hole it fits in that provides the tension on the extractor can fill up with an incredible amount of gunk. No offense here just want make sure we are using the same words for the same thing - the extractor being the part that hooks on the side of the shell casing and allows the bolt to pull the shell casing backwards. Short story - I have a Ruger 10-22 that started life as stock. After a few years there was not a single stock part left. I was obsessive about cleaning it. But I never removed the extractor nor the associated spring as "Hey, when I push on it it works according to my brain." Began to have endless issues with extracting, ejecting, rounds not feeding and jamming. Blamed the rounds, the magazine, the lube I was using etc. Purchased many lubes. "Tuned" the magazines. Spent hours on gun boards. Finally decided to replace the "never have to re[lace the super custom extractor with a new one." That's when I found all the gung in the spring and spring hole. Literally solidified gunk. Did a thorough muti-day clean, soak, clean, soak, clean. Put it back together and went to the range. Not a single issue even with the formerly "junk" magazines and "junk" ammo. Every last problem I had with extracting, ejecting and feeding went away. You mileage may vary.

 

[Andyd]

I have finally figured the problem out. The HK 4 had an extractor in it that was more of a dedicated centerfire extractor and did not apply enough tension on the rim. I have changed the extractor to one that did not work in an HK .32 but was too tight, not allowing the rim to slide in and suddenly both guns work.

 

[SkippySanchez]

I have finally figured the problem out. The HK 4 had an extractor in it that was more of a dedicated centerfire extractor and did not apply enough tension on the rim. I have changed the extractor to one that did not work in an HK .32 but was too tight, not allowing the rim to slide in and suddenly both guns work.

Wow, good work! That's very cool!

I'd give my right arm to be ambidextrous.

 

[Andyd]

We all know that without at least one photo, it did not happen. Here it is:


After I had the guns running, I took the time to read the original German manual, which differs from the English online version I have also found in the meantime. The cleaning rod has a screw driver tip and is perfect to unscrew the face plate.

I will compare the rimfire HK4 to a couple of other compact rimfire pistols in the coming weeks. So far, I find it to be a pleasant shooting pistol with very little recoil, despite the minute sights.

 

[UltraFudd]

Originally, there was one extractor (unmarked) for center fire, and one marked “22” included with a conversion kit.

I believe HK replaced this with a single, universal extractor at some point.

 

[rc51pete]

Originally, there was one extractor (unmarked) for center fire, and one marked “22” included with a conversion kit.

I believe HK replaced this with a single, universal extractor at some point.

Do you know how to identify the universal extractor? All of the information & pictures I can find are inconclusive.

 

[UltraFudd]

Do you know how to identify the universal extractor? All of the information & pictures I can find are inconclusive.

Wish I could. I know my 4-barrel original set (a 1968) only has one extractor which has worked w/ both rimfire and centerfire cartridges. Not sure if it was replaced along the way with a universal, but it’s good on extraction.