Thinking About a PTR-91

General Firearms Other Semi-Automatic Rifles
1

I’ve already got my dream AR 97% set up as I’ve always wanted, but as the title says, I’m thinking about picking up a PTR-91 for a proper “heavy-hitter MBR.” I’ve always wanted one - to my long wingspan, the ergonomics are great; the magazines are ridiculously cheap; the ammo is widely available; PTR has had a few years to work out most (if not all) the teething issues, and now makes most (again, if not all) of the parts in-house; even the wide handguards that used to be nearly impossible to find are easy to get. I’ve fired a FAL, M1A, AR-10, and even a Kel-Tec RFB (which choked on two of the five rounds I put through it and won’t be mentioned again), and overall I like the G3 design and feel the best of all of them.

As always, a few questions though:

  1. Extended maintenance - what springs and parts wear out often? What should I order to keep it running smoothly for 50,000 rounds - rollers? Main spring? Magazine springs? Is grease the best lube, or should I use oil?

  2. Optics - as a MBR and not DMR or other precision role, aside from irons I’d like to run a micro RDS on the permanently-installed Pic rail on the receiver. The most I’ve been able to find is from years-old discussions involving claw mounts. Would an Aimpoint T1/T2 be mountable for any sort of co-witness? Would they even hold up to the recoil impulse of .308?

  3. The lower portion (grip, safety, and trigger pack housing) that these seem to be released with currently look like something TAPCO designed, and I’m not quite convinced I like it. Reviews say that they’re functionally fine, but if I want to buy a “Navy” style lower or stamped steel lower, would they presumably be easily interchangeable?

  4. Several have talked about using a Heavy Buffer to reduce wear and recoil. Any input, criticisms, or praise for it?

  5. Sling. What are my options? Is the HK Claw style really the most recommended option, or can I get creative with IWC QD cups?

Probably more questions later as I think of them. Also feel free to post pictures of your setups, too, since the HK picture thread for this subforum seems to have fizzled out…

2

I picked up one of the PTR91s with a rail last year. I haven’t shot it a whole lot but I can answer some of your questions:

  1. Plus size rollers are recommended for long term maintenance as they can be used to adjust the headspace to bring it back into spec as the bolt, locking piece, rollers, and barrel extension wear. Other than that common spares like extractor, firing pin, and springs are good to have. You can get complete buttstock assemblies for way cheap* currently, which have recoil springs and buffers already installed.

  2. Aimpoint Micro co-witnesses with the stock iron sights, if you use a Aimpoint low mount.

  3. The lowers are interchangeable once they’ve been cut to fit a semi-auto receiver. I swapped mine out as I didn’t like the feel of the stock unit.

  4. The heavy buffer is probably overkill in a semi-auto rifle. You can also change the recoil force/opening timing by swapping locking pieces to a different angle.

  5. The HK 3 position sling is actually pretty well thought out, and works well on this rifle. You can always swap it for a Vickers or BFG and just use a HK or MASH hook up front.

Spares are crazy cheap and available** right now. It looks like the Germans and Pakistanis are dumping a lot of spares on the market now. If you’re going to get into it, get while the getting is good.

H

3

So I’ve done a bit of looking around and made the “mistake” of discovering the Vector Arms 94L. I figure if I get a PTR, then this (even though it’s over double the price) would be a neat addition to have too. The performance of 9mm out of a 16" barrel seems quite adequate, the same manual-of-arms as the 91, a longer sight radius than a usual MP5, less expensive ammo (though more expensive magazines), etc.

Anyone used or own one? Are these worth the price tag?

4

I picked up a PTR 91 GI about a year and a half ago to run as a KISS battle rifle. I really like it, but found I don’t shoot it nearly enough because it beats up the brass pretty badly, and I don’t shoot much .308 that aren’t reloads, and I’m looking to sell mine now. I’ll try to answer the questions that I can.

  1. Optics - as a MBR and not DMR or other precision role, aside from irons I’d like to run a micro RDS on the permanently-installed Pic rail on the receiver. The most I’ve been able to find is from years-old discussions involving claw mounts. Would an Aimpoint T1/T2 be mountable for any sort of co-witness? Would they even hold up to the recoil impulse of .308?

An Aimpoint T/H-1 or similar micro red dot should co witness on a wielded rail or claw rail mount.

  1. The lower portion (grip, safety, and trigger pack housing) that these seem to be released with currently look like something TAPCO designed, and I’m not quite convinced I like it. Reviews say that they’re functionally fine, but if I want to buy a “Navy” style lower or stamped steel lower, would they presumably be easily interchangeable?

Lowers are interchangeable. Mine came from the factory with the Navy polymer lower, and I replaced it with the older metal lower because I liked the grip better. The trigger packs are easily swapped from lower to lower if you do decide to change from one to the other.

  1. Sling. What are my options? Is the HK Claw style really the most recommended option, or can I get creative with IWC QD cups?

I run a padded V-Tac on mine with HK hooks. I never had a problem with the system, so I never looked at replacing it. You might be able to make QD mounts work. Hell, I got a Magpul MOE vertical grip attacked to the hand guard on mine.

I’d also recommend looking into the “Tac Latch” Mag release. The stock button isn’t particularly handy, and the Tac Latch is a good alternative to having a gunsmith do the work to restore the original paddle mag release. The PTR is a very cool modular weapon that lets you change it from a classy, wood stock look, to a modern, semi-camouflaged battle rifle with the polymer furniture.

EDIT: Older picture of my PTR, before I put the MagPul MVG or the Tac Latch on.

5

Something to be mindful of is that there are PTR 91s out there that simply will not work with 7.62x51. You must shoot only .308 out of them. I don’t know if this is still a thing, or if it would be much of an issue to you (I shoot almost exclusively Wolf or Prvi .308 through mine- it chokes on all 7.62x51) but keep it in mind.

6

How so? Chamber dimensions? Pressure differences?

7

Got one I’ll sell you. PM me.

8

Those were the older JLD stamped PTRs with serial numbers that started with A and AW. The chamber flutes weren’t cut deep enough. I had 2 of them.

9

Any of the newer GI models should work fine. PTR finally decided to get back to the original design when they released the various GI models.

10

I was seriously considering picking up one of these. Mags & parts are cheap and this would be a great time to get in if this rifle was what it could be. BUT, there are a lot of posts on HK Pro forum that indicate this is nowhere near HK spec. Bolts may be cast or MIM, same with hammer and other parts. Some of the tooling may be from HK, but it sounds like they abandoned HK spec and used whatever construction most cost effective. Reports of cracked trunion/bolts are particularly concerning along with non-spec barrel. Once you get through changing what needs changed, you would likely be better off with another platform.

11

I used to have one. Not a bad rifle. I ditched it to go the m14 route. With the grip frames you need to switch out the selector as well iirc. If you like the platform then go for it. They are serviceable but not to same quality as hk or a quality parts kit build.

12

I got one of the PTR91 rifles that CDNN had on sale back in December. It came with the cheapest scope mount and mystery scope but it did come with 10 spare mags and for a pretty decent price at $800. However, I did make a few upgrades by adding a wide handguard for better hand protection from a hot barrel and trunion, an HK21 cocking handle for easier cocking since the wide handguard does make it a little harder to get at the cocking handle. I also went with the heavy buffer to cut back on the snappy recoil of a roller lock design. Of course, I had to replace the cocking tube cap with a bayonet lug just to piss off liberals and for those drive-by bayoneting opportunities that may present itself. :stuck_out_tongue:

This right here though is the 2 biggest modifications I made to greatly improve the ergonomics. First, the selector lever is too short and too far forward to manipulate without shifting my grip. I don’t have the thumb of an orangutan so an extended lever from RTG made a big improvement here. Also, the M-16 style magazine release is just one step above worthless. Again, WAY too far forward to manipulate easily. I could have gone with the tac latch but I wanted to get that correct G3 feel to it so sent it off to Bill Springfield to have an anti-rattle paddle magazine release installed. I also got a pinned and clipped metal trigger housing just to add to the G3 look. Totally cosmetic here but looks a lot better. If nothing else, the selector lever and magazine release are the two “must have” mods that are truly needed on this rifle.

13

There are some threads on here and definitely on the HkCentric forum if search here doesn’t work that walk down the whole JLD/PTR timeline and address what serial numbers are what with known issues. Some A-prefix guns had tight chambers, but most work fine. Very early AW guns are fine, but the switch to TC barrels with shallow flutes around AW1500-200 or so caused issues with any tar-sealed ammo, which includes South African, Radway, Paki, DAG, and a bunch of others, including US made M852 and special ball. After blaming the issue on underpowered ammo for years, they went back to correct flute geometry with the GI model and across the line shortly after. All current barrels are GTG. As German parts dried up and domestic manufacture had to pick up the slack, there were some initial hardness issues with both bolts and trunnions. PTR replaced all cracked bolts or trunnions and eventually sorted out the metallurgy. There was a pretty good write up on one of the more manufacturing and engineering centric forums about cross sectioned hardness of PTR, RCM, and HK components, and it seemed the latest stuff is quite good. Anything after AW8376 or so and any new GIs should be fine.

From a practical side, I have 5 PTRs. 2 that had shallow flutes. One wears an RCM k barrel now, the other is a DMR and kept the TC barrel since it’s a sub MOA roller locker and I didn’t have the heart to change the bbl. out. One GI, which cracked the trunnion as one of the hardness problem guns, PTR fixed that in a week turn, and it’s been fine since. 2 are late production guns, Post AW8376 or so for an MSG91 in battle rifle trim and a 16" GI with a full length cocking tube. I recently acquired the second GI and don’t have time on it, but the MSG91 has been trouble free.

If they don’t have welded rails, they have MFI mounts bedded, but not glued, to the receivers with steel bed. All except the DMR with shallow flutes shoot all ammo just fine, including tar sealed and steel cased. The DMR runs suppressed most of the time with a #17 locking piece and a single stage heavy buffer. All have real paddle releases added. Just bite the bullet and get it done, it’s the way the rifle was intended to be run. The heavy buffers from Ghilliebear are GTG…he makes them by welding two stock buffer bodies together, turning a new piston and adding a new spring pack. They are also a lot cheaper than real heavy buffers and easier to fit in most stocks. The ESSL type SEF levers are useful…I have no problem with the selector unless I’m prone, but then the extended helps. YMMV.

While they are cheap, pick up extractors, extractor springs (You’ll likely ruin one or two of these detail cleaning over the years), ejectors, firing pin and spring, and a recoil spring or two. If you are going to mess with the trigger at all, pick up an extra hammer and sear. Then…Rollers… +2, +4, +8 are in my stash, along with retainer plates and pins. I have a ton of stuff, but it’s because I’m a roller gun nerd, not because I really need it.

I got into these years ago, when commercially available 7.62 AR variants were dubious, at best. I like roller guns, but if I were starting over, I’d probably have a couple to play with and be more heavy on SCAR or AR variants in 7.62. My G3k clone, though, is one of my favorites, and just a fun gun that is rather effective.

Mags aren’t 99 cents anymore like when I bought most of mine, but they are still so cheap that it just doesn’t make sense for us to bother making one. The gun is pretty forgiving as far as feeding, and I can’t say I’ve ever had a failure to feed, even from really messed up mags. It’s a big gaping hole to hit and an enormous bolt carrier slamming the rounds home, so it works. The BCG would likely also make a highly effective melee weapon. :slight_smile:

14

My A prefix was a decent shooter and only choked a handful of times. It shot South African, Santa Barbara(Spanish), and Port just fine. Just for grins one day I decided to shoot the remainder of Cavim I had around. It finally choked on the 17th round, but what gun wouldn’t. My 91KF(16") AW serial gun would choke on just about any 7.62 surplus NATO ammo plus the bolt appeared to be very soft. The newer ones have intrigued me though and it would be nice to maybe add another 7.62x51 gun to the stable. I enjoyed shooting the platform and the recoil wasn’t bad at all. The gun I really miss is my Springfield SAR8(NO, not the crappy aluminum one:D )

15

Great post. Thanks for the write up. Making me think I might pick up the GI model after all.

16

I have JDL that i bought during the AWB, with the A serial # 5_ _ it has been flawless 6,000 rd of nothing but Nato Mil-Surp ammo. Mines a keeper. I put a B-Squared scope mount on it and a Leupold 3X9 VX1 on it.

17

Duane probably takes the cake for posts on this but I will add one thing since it was mentioned.

Most PTR guns come with a lower that is not a Navy lower. They look like Navy grips, but I am almost positive that they are SEF/123style internals. SEF or 123 trigger packs are not interchangeable with Navy trigger packs.

So you can’t buy a Navy housing and drop in your trigger pack. You can put a complete Navy group on the gun however.

Someone please correct me if I mispoke.

18

I took my PTR trigger pack and put it in a semi-modified navy trigger housing. It works fine. I now have 1 safety positions and 2 semi only positions.

19

I have two. One 16 in barrel with telescoping stock. One 18 in barrel with wide hg, bipod, and fixed stock. I like them the way I like an old car. The ergs are so outdated. If they have one with a rail get it, I HATE the claw mount option.

20

I am with you 100%! All the great old guns are in the same boat: G3, M14, FAL, etc… They are all great basic grunt rifles. Left alone they do their intended role very well. Try to pimp them out to bring them forward into the 1970’s or beyond and you will be constantly chasing standards set by more modern designs and constantly disappointed. Trying to make those old classics have the ergos and performance of an AR is like putting lipstick on a pig.

All that being said, I still love shooting the classics.