Roller lock platform

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Steve_In_29
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Re: Roller lock platform

#16

Post by Steve_In_29 »

shooter444 wrote: February 12th, 2019, 8:03 pm
Pro2a wrote: February 12th, 2019, 12:43 pm
shooter444 wrote: February 12th, 2019, 9:00 am When I read about Savage's 17hmr and 22mag delayed roller lock semi-auto;s,... I was, and I am still tempted to buy, just because!

Now that you have my attention,... which 308 roller lock rifle are you talking about?
I dunno, I just see that it says in the intro to the article I pictured says 308 kits can be had for $600 with CETME parts.

I bought the Savage A17 when it came out, and haven't regretted it since. It's a roller lock, guess I already have that platform......
A friend turned my attention the the round long before that, and it was just about the time that articles were saying that Savage has figured out how to make a semi-auto hmr17 that doesn't jam.
After about 400 FLAT shooting rounds, I don't recall a single malfunction yet.
If you're on the fence, feel free to get the cobwebs out of mine sometime, and you'll be buying one.

Thanks,... but, I have read way too many complaints on CETME over the years, to take a chance on getting a good one.
He was offering you a chance to try out his A17...not a CETME.


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Re: Roller lock platform

#17

Post by Stronghand »

The PTR rollers are good to go. We just got the PTR 9CT and broke it in today as a post sample and it went 600 rounds without a flaw. We started off doing their break in routine they recommend but after 100 rounds and 3 cycles of breaking it down and cleaning on semi auto we said fudge it and rolled through the last 500 brrrrt after brrrrt. For a what $1600 street price MP5 it's great. Debating buying a 7.62x39 version and doing the same. My shop monkey has their G3 version in 308 and it runs great. If you want to do a old tyme 308 from the days of heavy shitty rifles go for it. Otherwise go build a nice 308 AR or take out a second mortgage and buy a SCAR.
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Re: Roller lock platform

#18

Post by knockonit »

I was sorting thru some brass yesterday and when i quizzed a gent that was working with me on it, the markings on some of the 9mm, he said it was from an mp5, as it leaves the long straight markings on cases, interesting guess we will see after cleaning and polishing and if they reload ok, or ...................

i would like me some mp 5 though.
Rj
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Re: Roller lock platform

#19

Post by Harrier »

Steve_In_29 wrote: February 12th, 2019, 11:03 pm
Harrier wrote: February 12th, 2019, 6:44 pm As a re-loader I dislike the chamber flutes left in fired cases from a roller lock G3 or PTR-91. They eventually flatten out but I still don't like them deforming the brass.
On better quality brass you simply get carbon streaking and not deformation.
Better Quality Brass ?? LOL come-on...
I've reloaded enough of it to have a different opinion...
The chamber is fluted and firing pressure will expand any and all brass to conform to shape- as part of the extraction system it is designed to provide more frictional delay, allowing pressure to subside before the rollers take over. It is essentially a blow-back system. If there are only carbon marks from the grooves, it's because the chamber is carboned up from lack of cleaning of blowback over several thousand shots.
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Re: Roller lock platform

#20

Post by Pro2a »

Steve_In_29 wrote: February 12th, 2019, 11:41 pm
He was offering you a chance to try out his A17...not a CETME.

:music-rockon:
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Re: Roller lock platform

#21

Post by shooter444 »

Harrier wrote: February 13th, 2019, 9:21 am
Steve_In_29 wrote: February 12th, 2019, 11:03 pm
Harrier wrote: February 12th, 2019, 6:44 pm As a re-loader I dislike the chamber flutes left in fired cases from a roller lock G3 or PTR-91. They eventually flatten out but I still don't like them deforming the brass.
On better quality brass you simply get carbon streaking and not deformation.
Better Quality Brass ?? LOL come-on...
I've reloaded enough of it to have a different opinion...
The chamber is fluted and firing pressure will expand any and all brass to conform to shape- as part of the extraction system it is designed to provide more frictional delay, allowing pressure to subside before the rollers take over. It is essentially a blow-back system. If there are only carbon marks from the grooves, it's because the chamber is carboned up from lack of cleaning of blowback over several thousand shots.



Agreed, Harrier,... I shot Remington, Federal, Hornady and Magtec factory ammo from my PTR and everyone had dented/flute marked shoulders, and everyone could be identified after full length sizing to reload.

The rifle functioned flawlessly and accurately for the many years I owned it,... but, like I stated earlier, the ergonomics sucked, for me!
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Re: Roller lock platform

#22

Post by brandyspaw »

It seems the Century guns have become a lot more consistent in quality these days. The older Century G3's and CETME's were spotty in quality as they were farmed out to different builders and used poorly
made receivers as well. So there was no consistency as some would function fine and others were just welded up messes with off kilter sights, ground bolts and other maladies.

I wound up buying a CETME from a dealer several years ago and had to return it for replacement twice before I got one that functioned correctly. Even then the welding looked horrible although it did work ok. My dealer at the time even stopped selling any delayed roller action Century's because he was tired of all the problems/returns. He still stocked a lot of the Century AK's but called it quits on the G3 type guns.

I still have that old CETME and its getting close to needing some larger rollers but it still running fine. At least it doesn't have a ground bolt and so it should be easy to correct the headspace. Its not so great on aesthetics compared to a real deal HK-91 but it does function fine.
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Re: Roller lock platform

#23

Post by Steve_In_29 »

Harrier wrote: February 13th, 2019, 9:21 am
Steve_In_29 wrote: February 12th, 2019, 11:03 pm
Harrier wrote: February 12th, 2019, 6:44 pm As a re-loader I dislike the chamber flutes left in fired cases from a roller lock G3 or PTR-91. They eventually flatten out but I still don't like them deforming the brass.
On better quality brass you simply get carbon streaking and not deformation.
Better Quality Brass ?? LOL come-on...
I've reloaded enough of it to have a different opinion...
The chamber is fluted and firing pressure will expand any and all brass to conform to shape- as part of the extraction system it is designed to provide more frictional delay, allowing pressure to subside before the rollers take over. It is essentially a blow-back system. If there are only carbon marks from the grooves, it's because the chamber is carboned up from lack of cleaning of blowback over several thousand shots.
Close but no cigar as to the operation of HK's roller-delayed rifle design.

Yes they are basically a blow-back operation BUT the delay is provided by the roller system and NOT the fluted chamber. The flutes are there NOT to provide extra drag to slow the movement of the bolt but to allow the gases to float the empty casing away from the chamber walls. The German engineers who originally designed the system for the Stg45 near the end of WWII found that absent the flutes the cases stuck to the chamber walls and the extractor simply ripped the case heads off.

If your understanding was correct then steel cased ammo (which I have never seen expand into the flutes) would cause the gun to cycle harder and lead to breakage. Which is not the case in my experience nor have I heard reports from the HK crowd of such concerns.

You are correct though that a dirty enough chamber will prevent even the softest brass from deforming. Yet even then the rifle will still keep functioning as the HK (unlike the AR which also craps where it eats) was designed to run DIRTY. I very rarely clean either of my PTRs and have never encountered a failure due to that. Though I can understand where more regular cleaning could be necessary for a sear host MP5 with its much higher round counts.

Yes, higher quality brass. My US military 7.62x51 brass doesn't deform into the flutes and just gets the carbon tracks as does some mil-surp from other countries. Commercial rounds and some lesser quality mil-surp brass (from foreign countries) does expand into the flutes.
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Re: Roller lock platform

#24

Post by Rock Hardson »

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Re: Roller lock platform

#25

Post by storage_man »

Steve_In_29 wrote: February 13th, 2019, 11:12 am Yes, higher quality brass. My US military 7.62x51 brass doesn't deform into the flutes and just gets the carbon tracks as does some mil-surp from other countries. Commercial rounds and some lesser quality mil-surp brass (from foreign countries) does expand into the flutes.
Steve is correct, better brass is not likely to see any flute indentations. But most HK's due to their violent ejection of a spent cartridge, will impact the case opening. I have a neighbor @ the Big Sandy that has several G3's & clones. His spot is 40' away from mine spot and I still get incoming spent cartridges.
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Re: Roller lock platform

#26

Post by knockonit »

lol, we were out shooting a few weeks ago, and dragonfly was shooting a cetme, it flew brass a good 40 ft at about 5 o clock from him, funny as all get out, the mp5 was awesome to watch, a steady stream of brass flying ever so lightly out and away.
me like me some mp5
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Re: Roller lock platform

#27

Post by lew »

Harrier wrote: February 12th, 2019, 6:44 pm As a re-loader I dislike the chamber flutes left in fired cases from a roller lock G3 or PTR-91. They eventually flatten out but I still don't like them deforming the brass.
I reload all the brass that goes through my PTR. The flutes pose no issue to reloading and the brass functions fine in my other 7.62/.308 rifles.
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Re: Roller lock platform

#28

Post by shooter444 »

lew wrote: February 14th, 2019, 10:24 am
Harrier wrote: February 12th, 2019, 6:44 pm As a re-loader I dislike the chamber flutes left in fired cases from a roller lock G3 or PTR-91. They eventually flatten out but I still don't like them deforming the brass.
I reload all the brass that goes through my PTR. The flutes pose no issue to reloading and the brass functions fine in my other 7.62/.308 rifles.
Hey lew,... I agree with you that dented shoulders don't cause any function problems,... but, as Harrier stated, I DISLIKE the dents, as he does!

I prefer my cases having the ability to expand and seal. I have a tendency to question whether the sealing of gases isn't compromised, even in a small non problematic degree when case shoulders don't expand and conform 100% to the chamber.

I know, I know, it doesn't effect the reliability. I just didn't like it, and it was one of a MAJOR factors in my decision to trade it off.

To each their own.
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Re: Roller lock platform

#29

Post by Steve_In_29 »

shooter444 wrote: February 14th, 2019, 10:36 amHey lew,... I agree with you that dented shoulders don't cause any function problems,... but, as Harrier stated, I DISLIKE the dents, as he does!

I prefer my cases having the ability to expand and seal. I have a tendency to question whether the sealing of gases isn't compromised, even in a small non problematic degree when case shoulders don't expand and conform 100% to the chamber.

I know, I know, it doesn't effect the reliability. I just didn't like it, and it was one of a MAJOR factors in my decision to trade it off.

To each their own.
Almost 8 MILLION HK G3's (not counting semi-auto HK91s/PTR91s/SAR8s/etc/etc) have been produced from 1959 until the present day and the rifle was used by 87 countries around the globe at one time or another. With G3s still being used in military service to this day. The HK PSG-1 that utilizes the same fluted chamber is one of the most accurate semi-auto sniper rifles in the world and is still produced by HK.

Any "compromise" is simply in your head. There is nothing to be concerned about with the design nor anything to cast aspersions on. Though whether or not you like the rifle is another matter and obviously your choice.
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Re: Roller lock platform

#30

Post by shooter444 »

Exactly,... I DIDN'T LIKE IT!!!

But, contrary to many nay-sayer's,... I ACTUALLY OWNED AND SHOT ONE FOR YEARS!!!

I don't give a s*** how many were produced or what the overall reputation is,... I hated the bolt release ergonomic, I hated the trigger, I hated the mag release position / ergonomic, I hated the sights, I hated the scope clamp mount, and I hated the poor balance / weight ergonomics!!!

Basically, I believe there is not much to like with this weapon,... and, that because of that, it is basically a conflict weapon that is put in the hands of those that don't have any say about what they like or dislike,... period!!!

I don't care how many million people like the millions made,... I hated the one I owned and shot.

jmho
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