What kind of groups can be expected from hk/ptr 91s

A stock, no-frills HK91?

2.5 MOA or so.

Yes, PTR owners constantly squawk about how their rifles are sub-MOA, but I have never seen it done in person. Keep in mind that for HK to get there, they had to reinforce the receiver, extend the trunnion, use a different barrel (with different rifling too), use a completely new trigger, redesign the bolt head, and use titanium crescent-shaped rollers.

2.5-4 MOA.

This is the internet though, get ready to be told that "their rifle" is sub MOA.

My HK91 is a 4 moa rifle with typical 7.62 NATO ball ammo. Maybe a little better with PMC Bronze .308. It will do a little better here and there, but that's been my experience so far. I have yet to try any quality match ammo or hand loads. 

Also using iron sights FWIW. 

Would the ptr msg be capable of 1 in groups? Or is it just a decked out ptr91

The best I've got with my PTR GI was 2.25. 2.5 is more realistic.

I highly doubt it.

Look at all the improvements that the PSG1 and MSG90 had to implement to get to 1MOA. PTR's top of the line rifle lacks the most essential changes.

mine gets about 2MOA sometimes a little less with my reloads which it likes,Trigger is a PSG1 trigger though.
with MILSURP it is closer to 3.5MOA sometimes 4MOA,

Triggers are a big issue on 91's along with it's other parts as some one alluded.

I still lie it cause it has always gone BANG,Looking for brass ids fun too

Also depends on the ammo you’re using.

Had a stock PTR 91 that I got down to 2 +/- shooting handloads off a bench at 100 -200 yds.
That was about the best I ever got from that rifle.
A whole lot of fun though...

I have owned and shot 17 different HK91 style rifles from 3 production facilities, built from the 60's thru the 90's.  None from PTR.  Only a single example would beat 2.5 MOA from a rest, most were 4 MOA.  That was a PSG1 from Germany and the best I got from it was 1.25 MOA.

These aren't precision rifles, they are BATTLE rifles.  I had one with tank track marks on it that still functioned.  Amazing.

I think there are some examples of williams set triggers producing repeatable trigger pulls.  The chambers are not amazing the claw mounting systems aren't great and they would beat the shit out of your brass in the process.  In the end what is the point?  You can get so much more gun out of modern sporting guns now.

My best from a PTR is around 2.5" using FGMM. I'm thinking a good part of that was luck. With ball ammo I was typically closer to 4.5". All at 100 yards.

This right here, like FAL, there 4 MOA guns shooting 6MOA ammo by 10 MOA conscripts...

A friend shot his Springfield Portuguese 91 clone (the one with the crappy pinned California compliant brake) in front of me. Five shots the size of a quarter at 100 yards.  The gun might be a fluke but he's a good shot.

pics?

I tried all my best when I had an hk91 to make it "accurate" and even with handloads I was still barely even getting 2moa.  Nato ammo was minute of car door and I was more interested in seeing where the brass shot off to than where the bullet went.

an old friend of mine had one of the early JLD PTR's that i've taken to believe were a bit more accurate than current rifles because they had a heavier barrel profile and different rifling...

that gun was 2-2.5 MOA.

not bad.

The standard battle rifle trigger on a G3-type rifle is a huge impediment to accurate shooting. For example, my old FMP G3S had a no-shit 17lb trigger pull. Now this is heavy even for a typical G3 rifle, but even the best ones had to be paratroop drop-safe. This meant that the triggers were very heavy.

A word of warning: stay away from the work of a gunsmith with the initials ‘BS’, no matter how good his claims sound to you. I have a trigger pack in my parts box that was ruined by him, and the Mickey-Mouse work that was done to it made a gunsmith friend of mine laugh and cringe at the same time. Lots of meat missing from the sear and hammer, the trigger return spring wadded-up behind the trigger, etc.

The local Arfcommer who gave it to me was the one who sent it off to BS, and it came out of his Springfield G3(NOT SAR-3/SAR-8). He found out after getting the part back that his rifle had a 4.5lb trigger on FIRE, a 8lb trigger on SAFE(yes, it would fire when placed on safe), and best of all, he could make it fire by wiggling the trigger housing a certain way. I could not replicate the third issue in my rifle, but the modified trigger was the only way he and I found to make our rifles unreliable. Lots of reset issues that weren’t there when we put our unmodified trigger packs back in.

I don’t know if the guy's work has gotten any better, but his solution to my buddy was ‘send me your trigger housing, I’ll make it work’. No offer of a refund or replacement of his trigger pack, but instead doubled-down on his crappy job.

Caveat Emptor.

We got our first one.

What ammo?
Scope or irons
Bench rest
Upgrades?

I'm calling BS.

My hk91 is probably 3-4 moa and I wouldn't trade if for nothing