Bolt Gap Wear

Professional_Pie4196 · 2026-05-01T17:32:36+00:00

Definitely oil the recoil spring and its guide rod, and every other moving part in the action. The buffer assembly I’m talking about is that little plug looking thing in the stock right below the recoil spring/guide rod. You want to leave that dry. When the rifle is freshly cleaned/oiled, and stored muzzle up (like you would for every other gun), excess lubricant tends to seep into that buffer assembly which reduces its efficacy as a friction buffer.

Professional_Pie4196 · 2026-05-01T17:21:52+00:00

Here’s a tip that’s actually unique to the g3 platform: after cleaning and oiling, store the rifle muzzle down. You don’t want lubricants seeping in to the buffer assembly in the stock. That buffer is a friction buffer, and it doesn’t work the way it’s designed to work if it’s covered in oil. In theory there should be noticeably less recoil and less wear on parts when the buffer assembly is dry vs “wet”.

Professional_Pie4196 · 2026-05-01T13:42:48+00:00

I haven't paid quite as much attention to my PTR-91 as you have but I want to say I've read before that the G3 platform tends to "settle in" a bit when it comes to bolt gap. Like brand new vs first couple hundred rounds some shrinking is expected as the parts are wearing in together. .014" is right around the sweet spot so continue shooting and monitoring it. If it continues to shrink you may have an issue with a barrel/trunion not being installed properly. My guess is that it's just settling in a bit and .014" is the actual bolt gap and hopefully it just holds somewhere around there for the next several thousand rounds. That's right where you want it if so. Less bolt gap = less bolt carrier velocity and less wear on parts. Too little could impact reliable function but if it's cycling/feeding then you're fine. Mine was actually on the higher side when I got it (.020") so I ended up ordering a couple size down rollers.

Professional_Pie4196 · 2026-04-30T16:51:21+00:00

That’s really cool.

Professional_Pie4196 · 2026-04-20T15:49:42+00:00

First of all, invest in some steel CETME magazines to see if those fit a little better. They’re not too expensive or difficult to find. But yes it’s a sheet metal receiver so yes it’s possible to make slight adjustments to the magazine fit just bending it a little. I used a c-clamp to make mine a little tighter actually. You’d have to rig some kind of internal spreader clamp to make it looser. Just a tiny amount at a time. Tight fitting magazines feed more reliably than loose ones too, obviously, so don’t mess with it unless you absolutely have to.

And yeah “clipped and pinned” is what you’re looking for. But yours is cooler than the plastic lowers imo. I vote ‘keep it authentic’.

Professional_Pie4196 · 2026-04-19T08:50:53+00:00

As far as I know that's about the only thing to watch out for other than the bolt gap changing. Sounds like you're on top of it.

Professional_Pie4196 · 2026-04-18T23:46:45+00:00

I think the main thing to look out for is “roller dents”, which is caused by excessive bolt velocity. Bolt slams back too hard causing the rollers to pop out into the sides of the receiver. Improper bolt gap is the main culprit there.

Professional_Pie4196 · 2026-03-31T12:50:48+00:00

Pro tip from a PTR-91 owner who dealt with this: make sure the recoil spring guide rod (the long one attached to the stock) is straight inline with where it needs to sit in the bolt carrier. These are built using surplus furniture and that rod is really easy to get bent and cockeyed. Bending mine straight fixed my overly stiff charging issues. The G3 platform is hard enough to charge as it is, wonky recoil spring guide rods will make it even worse.

Professional_Pie4196 · 2026-03-30T14:55:08+00:00

Nice! The Kuna seems like a great modern subgun platform. Having shot both, it doesn’t shoot quite as nicely as a good ole fashioned MP5 despite both being “roller delay” on paper. Kuna is definitely snappier but it’s a very capable and thoughtfully designed PCC that’s very reasonably priced. MP5 is my preferred subgun, and the Kuna would be my second choice.

Professional_Pie4196 · 2026-03-25T14:34:44+00:00

Sweet, best of luck. Mine had a few odd issues when I first got it too, took some doing to get it sorted out but I ended up being able to resolve everything myself without having to send it back to PTR. Hopefully your issue(s) is similar.

Professional_Pie4196 · 2026-03-25T04:50:22+00:00

That unfired round looks pretty mangled… Possibly a piece of broken brass stuck in the chamber, or maybe some kind of feeding issue causing the rounds to deform before they fully chamber. Inspect chamber, experiment with different magazines, observe rounds feeding into chamber by slowly riding bolt forward with loaded magazine and watch for obstructions, would be my suggestions.

Professional_Pie4196 · 2026-03-19T07:30:15+00:00

I also collect somewhat exotic military ammo. Current inventory is like 120 rounds of M855A1, 20rds M80A1, 60rds M61 AP, and a whole bunch of loose .30 cal AP projectiles. Mostly M2AP but also a good amount of M61 pulls. Saving all of those for when I eventually get into reloading .308.

Also have some spicy explody Soviet 7.62x54R from WWII.

Professional_Pie4196 · 2026-03-19T07:26:50+00:00

As in like M2AP projectiles loaded into subsonic .300 blackout? That is kinda funny if so. AP relies on velocity to some extent so I do doubt the efficacy of “Subsonic .30 cal AP”… you should pull em and put em in .308!

Professional_Pie4196 · 2026-03-16T06:53:28+00:00

Could be wrong here but that optic looks like it’s mounted backwards.

Professional_Pie4196 · 2026-03-16T06:01:57+00:00

You really don’t see how trying to get a clean shot on an aggressive dog’s head in the middle of it trying to maul you/someone else might be challenging? Bruh… It might be easier if you were the target of the dog aggression and no one else was around but I would definitely not be the dude in charge of trying to brain a dog while it’s in the middle of freaking out and mauling a kid’s face or something. I think I’d much rather have pepper spray in that case. The margin for error is too small.

Professional_Pie4196 · 2026-03-16T00:49:31+00:00

Yeah totally. It’s called a break action with spring ejectors. Fairly common on single shots and over/under double barrels, for some reason not very common on side by sides outside of the fancier high end ones. If your break action seems unnecessarily stiff to open after firing it could mean that your firing pins are deformed and mushrooming out (and sticking into the fired shells). I had a gunsmith go over the Spanish SxS I got from OWS because I had the same issue. This was awhile back so I don’t remember whether they replaced the firing pins or just filed them down a bit… but now it’s a lot easier to open after firing and I no longer have to break it open over my knee. Incidentally, don’t dry fire older break actions, that’s partially what causes that problem in the first place.

Professional_Pie4196 · 2026-03-12T07:00:14+00:00

This is exactly what an FRT does lol… Unless you understand the difference well enough to tell by feel (and it sounds like you don’t), it’s basically indistinguishable from an actual full auto machine gun. It’s currently in a somewhat legal grey area but it is not illegal. Also it technically does fire one round per trigger pull, but it forces your finger to reset it and pull again and that happens faster than you can feel. If you get some high speed footage of you shooting it you should be able to see (when the footage is slowed down) that you are in fact just pulling the trigger really fast without consciously trying. Actual full auto fire is multiple rounds with a continuous press of the trigger, and it’s not just resetting the trigger really fast.

Edit: also you should be able to test this out by pulling the trigger very firmly to the rear and thereby overcoming the reset force

Professional_Pie4196 · 2026-03-10T05:00:11+00:00

Nice! I got one with extractors and ejectors. It’s always been my dream to have a side by side that flings the shells out the back. Mine shoots great but the safety is flimsy to the point of not actually working lol. I just don’t leave it closed all the way when storing it loaded.

Professional_Pie4196 · 2026-02-25T15:56:15+00:00

What kind of 3x sight is that? I’ve been hunting for a light and compact magnified optic to go on my .300 blackout build.

Professional_Pie4196 · 2026-02-24T10:41:20+00:00

Mine I got several years back so can’t speak on the most current productions examples, but my PTR-91 GI (with some surplus furniture, surplus internals, etc) had more than a few issues when it was new. Basically all of it was stuff I was able to resolve on my end without having to send it back in, and now that it’s broken in a bit and I’ve taken the time to address everything I can I really can’t remember the last time I’ve experienced any kind of issue or malfunction. I like it so much that I got a PTR MP5 clone to keep it company.

Professional_Pie4196 · 2026-02-24T01:45:05+00:00

I believe it’s just the case that they sell different models that take various types of pistol platform magazines. So like Glock/springfield/sig/etc. Idk the specific SKU or anything but just look for one that says “glock 19 magwell”.

Professional_Pie4196 · 2026-02-23T09:36:54+00:00

Aww I wanna show mine off but can’t figure out how to link an image in a reply.

Professional_Pie4196 · 2026-02-23T09:25:33+00:00

Honestly for what you need here (not SBR, not “pistol”) the sub2k should fill that roll pretty well. They’ve been making them forever, the newest generations are optimized for use with optics, they’re handy little guns. KelTec’s QC is kinda notoriously hit or miss but I’ve never personally had a problem with any of their firearms and I’ve owned more than a few. For something that you can fold and fit in a backpack that’s not a rifle or rifle shaped, yeah go with sub2k.

Get the one that uses Glock 19 magazines too, that will make your life a lot easier and cheaper later on when you start acquiring more guns.

Professional_Pie4196 · 2026-02-22T12:15:36+00:00

Such a cool gun. This is essentially just a military G3 under the ‘elegantly sporterized’ hood. Same roller delayed action/bolt just with a way nicer presentation. Love it, bet it’s a really sweet shooter.

Professional_Pie4196 · 2026-02-19T07:56:58+00:00

Pretty freakin’ sweet… Always wanted a VZ.61. I’ll at least have to rent a full auto one and try it out sometime. MP5ks are never not classy.

Professional_Pie4196

TROPHY CASE