I picked up a PTR-91 a couple of months ago without doing any research beforehand. I bought four boxes of 308 Winchester Federal Power-Shok 150 Grain Soft Point ammo to try it out with initially. I sighted in the rifle within 20 rounds and put another 40 rounds through it without a hitch. Cleaning the rifle wasn’t a big deal except for putting the bolthead back on the bolthead carrier properly. I found the following HK G3 Disassembly instructions on www.MG-42.net. The information made putting the rifle back together a lot easier. If you have had any issues putting the bolthead back on the carrier then I recommend this bolt assembly tool. After cleaning the rifle I thought I would not have any issues with it for a long time and then…..
I bought a case of PMC Bronze 308 / 7.62 Nato for the rifle and that’s when my firing issues started.
My PTR-91 did not like the PMC ammo even though it was brand new and commercially produced . It would fire one round, the rifle would cycle the next round and then fail to fire the following round. I tried about a dozen times and it would do this for every round that the rifle cycled. The only time it worked was when I manually worked the action. I thought that this was strange and cleaned the rifle and put it off to the side until I could call PTR.
I called PTR and they asked what kind of ammo I was using and they said that the PMC Bronze would be fine. The PTR rep sent me a new firing pin and spring. After installing the new firing pin and spring the firing issue was not fixed. At this point I went online and quickly realized that a lot of people were having problems with their PTR rifles. I came across forum posts about the PTR being picky about certain types of ammo. Here is the list that I’ve seen online.
- South Africa
- Winchester white boxes marked 7.62
- Venezuela Cavim
- Austrian (Hirtenberger)
- Some lots of German
- British (under powered) will not cycle action
- Indian (Over powered)
I also checked the headspace on my rifle with this feeler gauge from Amazon.com and it was within the recommended tolerance of .004-.020 at .017. I had all sorts of issues trying to figure out how to measure the head space on the PTR-91 until I found the following instructions to check the head space on a PTR-91.
- Let the bolt and carriers snap forward on an empty chamber
- Set the weapon to fire
- Pull the trigger
- Measure the gap between the bolt head and the bolt carrier should be .004-.020
Since my ammo was not on the list but it was sold as 7.62 / 308 winchester I thought it might not be to 308 spec so I switched back to the expensive Federal 308 ammo and the rifle worked like a champ. I then tried my friends PRVI 308 military surplus ammo and it went through it with no issues. I also used Winchester 308 hunting ammo and it went through it all up except for one misfire. For the final test I loaded a mix of all three types of ammo in a 20 round magazine with 19 rounds and fired the whole thing off without any issues. I’m going to test the rifle some more this weekend a write up my final opinion on the ptr-91 next week.