I must be way behind the times when it comes to tinkering with these rifles.

I wasn't aware that they made a conversion kit for the HK 91 - that's pretty cool!

I watched a couple of videos where they were firing it on full auto - those little rascals were coming out of there pretty good.

I would say that if that's the rifle you use to hunt with, it would certainly make sense to got with the conversion as a money-saving option while still using the same gun.

If you use something else for hunting, simply shooting a .22 is still a good idea as you are practicing the basic shooting skills (sight alingment, trigger and breath control, etc), while shooting much more economical ammunition.

I don't personally do it, but it's a good idea.

I’ve never seen them in full auto and don’t plan to!  I have a severe allergy to prison stripes! But they are fun to plink with.  The technology isn’t new.  If you are behind the times then you are 50 years behind the times, since my conversion kit dates to 1950s or 1960’s German military issue.  The PTR civilian variety of the rifles are a newer production of course, but I don’t think anyone is making the conversion kits.  That’s why the silly things are so expensive.  Sportsman’s guide had these for sale at $539 plus shipping and handling the last time that I checked.  They are still making conversion kits for AR 15 style rifles so they are a LOT cheaper.  But I’m not a fan of the AR platform.  The HK style rifles just seem to fit me better and point more naturally for me.  Maybe its genetic, one branch of my granddad’s family was traced back to a little village in present day Germany.  But we left in the 1500s……..

But I digress, when the price of ammunition was going out of sight and I realized that I could save 20 cents or more on every trigger pull by shooting 22 instead of 7.62x51 (aka 308 Winchester  - yes I know there is a technical difference but really for all practical purposes they are the same!) I took the plunge and plunked down the cash.  It will take me going through two thousand twenty two cartridges to break even, but the conversion kit and the rifles should last a lifetime. 

I think they are a neat way to introduce kids and spouses to full sized military rifles too.  At the bench weight is not an issue and when using the 22 cartridges there is no recoil at all, so they can get used to the feel and controls should they ever want or need to use the full power cartridges in the same or a similar rifle.

As a side note – these conversion kits will not work in the Spanish Cetme rifles (or the recent classic Arms remanufactured Cetme rifles).  They are externally very similar to the HK91 being the immediate fore-runner to it, but they are just different enough inside that the conversion kits won’t drop in to the Cetme receivers.

I shoot thousands of .22 rounds a year for cheap practice for trigger control and different types of shots at small targets that I could not afford to do with my hunting rifles.

I also use an Advantage Arms conversion for my Glock29. Same trigger and holster but a ton cheaper than a box of 10mm shells.

Here's a photo of the kit