Very aware of all the adjustments on the gun, but it would not cycle properly using the suppressor on any of the settings. POF recommended it be sent to them.
- Thread starter Ape_Factory
- Start date
This guy chambered one in 27 RPR (necked up and blown out shoulders on a 6.5 CM)
mdws.forumchitchat.com
Ruger SFAR 308 ?
https://ruger.com/products/sfar/models.html Any one know what bolt and extension this uses? An AR15 with a long mag is what I am seeing. Any more info?
mdws.forumchitchat.com One of the local gun ranges had a sample of ballistic glass that had been shot with several different rifle calibers. Out of 7 or 8 rounds only 2 penetrated the glass. The .308 and can't remember the other. The 6.5 did not penetrate.
Yeah I’ve shot ballistic glass and without details that’s a pretty useless test as bullet construction is a main consideration.
Don't know any details other than each spot on the glass was labeled with the type bullet used.
I've read varied reports with regards to accuracy and reliability with this rifle.
Do you think the 20" version would suppress well? ARs run better with longer barrels and tubes, right?
Do you think the 20" version would suppress well? ARs run better with longer barrels and tubes, right?
I am seeing a lot of problems with the SFAR. There is a thread on ar15.com with lots of problems like:
- the gas block contacting the rail
- not cycling
- finicky when it comes to ammo
- not the greatest customer support from Ruger
Lots of people over there are swapping out the gas blocks.
I do not have anything that fires .308 and would like to change that. My first choice was a Scar 20s but I do not want to spend that kind of money. I do not understand how FN came up with the MSRP on all their Scars. I am also not going to shoot it all that often.
I see the SFAR and like the price. I do not like some stuff on the gun like all the holes in everything. I am seeing the problems with and asking does spending another $600 on the Rogue eliminate those problems?
POF rogue is probably worse odds, I'd take a chance on a used 14.5" POF piston 308 though I like that size
I bought a used 716i just to have an AR10 plinker but a basic armalite would be good too
Some will poo-poo the idea but if you just want a .308 rifle get one of the PSAs. They are around $700ish for a kit and stripped lower. If it isn't as accurate as you like, swap in a better barrel and do the accurizing tweaks.
PSA is not an option for me. They will not ship anything - and I mean ANYTHING - to MA.
Buy something used off Gunbroker? That's how I found my 716i. Googled for the gun store and then haggled with them over the phone.
My sfar has been rock solid. Easily my favorite pig gun. Zero issues. Very accurate with fgmm 168's. No brainer for $950
16" or 20" ?
There's a thread like that here.
Two of us are sending the rifles back to the mother ship, mine is a 20" and I think his is 16" IIRC.
Both are chewing up brass bases and mine popped the primers out of 3 Rem Core Lokt rounds on gas setting 1 suppressed
My cycling issues have been minimal (over gassed so go figure) and the accuracy was very good with a variety of ammo
Ruger SFAR chewing brass
Got a SFAR, and I noticed it was chewing up some of the case heads on the brass. Plus always had a flyer in all groups. Anyway, contacted ruger, great service. Sent off and returned on thier dime in about 10 days. New barrel and BCG. Shot some more, and still doing it, but not as bad and as...
www.snipershide.com Last edited:
That's my understanding and a hellalotta gas comes out of the front two plus the smoke coming out of the charging handle looks like a genie coming out of a bottle.
Somebody out there already milled a new barrel for his SFAR and changed the caliber
Just noticed AXMC posted this first and I missed it earlier.
Ruger SFAR 27 RPR
20 inch rifle gas 27 RPR -- 6.5 crymoor necked up and shoulder blown to 40 deg.
Ruger SFAR 308 ?
https://ruger.com/products/sfar/models.html Any one know what bolt and extension this uses? An AR15 with a long mag is what I am seeing. Any more info?
mdws.forumchitchat.com Last edited:
I can see the stake marks but they're obviously meaningless.
ETA: This is 1000% normal for a 308 AR, his ammo is too hot.
Mine is due to reach the mother ship Monday the 3rd but I believe they will be closed for the week.
Last edited:
Ruger SFAR 20" purchased in June. Took it out to shoot a variety of OTS factory loads for required break-in.
About 80 rounds in I shot 5 rounds of Rem. Core-Lokt suppressed on gas setting 1 and it popped 3 primers. I didn't notice until all 5 rounds were fired.
The base of nearly every piece of brass is also chewed up. It has been sent back to Ruger.
ETA: I went as far as to split open one of the cases that popped a primer, even ended up polishing the inside and after dozens of minutes staring at it then soliciting opinions the conclusion was no visible pressure signs. So maybe unlocking early (sometimes?) but just enough to leave the primer unsupported.
Last edited:
Being 180gr Core Lokt probably has something to do with that. The brass extrusion into the ejector channels is extremely pronounced with that load. Would be interesting to see what it does with the gas shut off with that ammunition.
I like the idea, it's a suggestion worth testing. I wish I'd thought of it while I was there. When it gets back I'll try a couple of everything on 0 to find out.
FWIW, I also put PPU 145gr, PPU 165gr, PPU 180gr, Rem 168gr (nickel plated "Hog Hammer") through it the same day. They all suffered similarly, granted maybe the Rem 180 a little more but there's quite a few 145s with chewed up bases as well but no loose primers I know about. Maybe I'll poke at the primers on the rest of the cases with a bamboo skewer to see if any drop out.
What's interesting is it's not consistent at all. That case front and center in the pic above is cleaner and less damaged than the others. It's the same for all the rounds I shot, some more damaged than others.
When the bases on 145 and 168 are getting chewed up what what's left to shoot?
When it comes back maybe I'll put a couple training rounds through it and see where that goes.
Shipping question, anybody know what happens when Ruger is closed for a whole week and FedEx tries to deliver? I guess there's a chance it might come back to me and have to be shipped again.
FWIW, I also put PPU 145gr, PPU 165gr, PPU 180gr, Rem 168gr (nickel plated "Hog Hammer") through it the same day. They all suffered similarly, granted maybe the Rem 180 a little more but there's quite a few 145s with chewed up bases as well but no loose primers I know about. Maybe I'll poke at the primers on the rest of the cases with a bamboo skewer to see if any drop out.
What's interesting is it's not consistent at all. That case front and center in the pic above is cleaner and less damaged than the others. It's the same for all the rounds I shot, some more damaged than others.
When the bases on 145 and 168 are getting chewed up what what's left to shoot?
When it comes back maybe I'll put a couple training rounds through it and see where that goes.
Shipping question, anybody know what happens when Ruger is closed for a whole week and FedEx tries to deliver? I guess there's a chance it might come back to me and have to be shipped again.
Makes me wonder about headspace if it’s doing that to everything. Lots of hammer effect maybe? Sorry if I missed it but did you check the headspace with gauges or Hornady Comparator? Check before and after firing. You’ll have to shave off the extrusions to get proper measurements.
If fired brass looks like a balloon I'd suspect excessive headspace, a beat up case head I would think a combination of overgassed/hot ammo/sharp edges on the bolt face, extractor, ejectors etc.
Interesting thought, also something I hadn't considered. I think I have a comparator buried in a drawer somewhere from back when I could find and was willing to pay for primers/powder. Been shooting squirreled factory nuts for a while, no reloading.
Using the comparator to measure what passes for the datum for Hornady I get 1.622" for an unfired round and 1.628" for one of the ones with a popped primer. Trying to measure one of the fired rounds that still has the primer doesn't work because even on those the primer is bulged out.
That’s only .006” movement after firing, which doesn’t indicate a headspace problem. Did you thoroughly remove the burrs from the ejector channel extrusion before getting those measurements? If so, I don’t think we’re looking at a headspace problem, and can then focus on the gas system, plug dwell time, and port diameter.
The next likely inevitability is that PPU and Remington brass is notoriously soft, so you might have to write those off as incompatible. For me, I think I would only want to shoot Lake City, Winchester, and MEN brass off the top of my head.
I wouldn’t want to be Ruger CS and QM right now.
Oh hell no
I measured 2 cases, there was a clean flat spot between the burrs but I'll clean one up and measure again. I got an email that the rifle arrived yesterday so there's time to fiddle with brass.
The thing about the brass chewing is it's not consistent. The spent case front and center in the previous picture was fired along with the other four on the same gas setting with the same suppressor all just seconds apart from each other. Same type of burring intermittently happened with the lighter PPU cases both suppressed and unsuppressed ... I need to go back and check those for loose primers. Two of the primers in those Rem cases just fell out but two others were loose in the pocket.
Besides the inconsistency in burring and primer popping I just don't personally know anyone else with a 308AR that chews up brass like this or pops primers. My other 308AR dented case necks pretty good before I replaced the gas block with an adjustable. Now it's fine but it weighs nearly 3 lbs more than this one thus the desire to switch.
Someone might say "well, uh, dems dare ammo is jus too *hot* fo dat rifl" but that is near tantamount to saying this rifle is potentially not safe for factory loaded 308 Win. which is almost like saying it's only safe for punching paper with MilSurp ammo.
Did Ruger just release the "308 Govt." (e.g. 45-70 Govt.)? They need to put a caution label on it for what ammo to avoid.
When it comes back I'll take it out again "as-is" from CS and if it's not up to my expectations I'll replace the gas block with something "infiinitely" adjustable and schlep it to the range with with an assortment of buffers and springs in hopes of taming it down. ETA: If I can improve things considerably with a block, a buffer and maybe a spring then I'll start looking for a way to improve dwell time but everything behind the shoulder is around 0.628" so I'm not exactly sure about how to approach that one. I don't think my old Liberty Freedom will index off the muzzle, maybe I'll hit Dave up to see if he has any ideas.
If I can't get it to work right I'll put a label on it that says "MilSurp ammo only" and sell it for $600 in the H-E-B parking lot.
Last edited:
This is the problem with .308 gassers. They have to be able to run on underpowered 147 ball. Or the CS phone will be jammed with people complaining about how it won't run Wolf. Then when you use something with some horsepower you're over gassed.
Maybe they have to re-think that gas valve again? At least Desert Tech listened, lol. I think I would put a SA AGB on it if possible.
Yeah, the previous 308AR settled down with a JPE AGB, shoots everything great and tears up nothing. I set it to cycle the lightest stuff I shoot, the hotter stuff comes out dirtier but unmolested.
I think I have an old Seekins blcok aorund here somewhere but I'm old so it could be an SA but if I don't find it in the next couple days I'll order one just so I can put it next to the other one I can't find.
I like to think it has a chance of coming back from Ruger working the way I want it to but I also buy a lottery ticket once in a while.
Speaking of things that sound insane.
Obligatory I'm not a gunsmith disclaimer.
Somebody explain to me why a rifle with a bolt the size/weight of an 5.56 bolt needs gas ports and a spring bigger than the average AR308 to cycle.
I mean, I understand it's a bigger boolit, more gas, more power, arr Arrr ARRR and all that shit but when it comes down to it shouldn't it require about the same amount of gas to cycle a bolt that weighs the same amount as an 5.56 bolt even though it's shooting 308?
What size is the gas port for 300BLK compared to 5.56? What's the difference in the weight of the bolt for 300BLK vs 5.56? Is the spring different? The buffer?
There is no difference in the weight of the bolt . 5.56 and 300 blackout use the same bolt .
My thinking on it. Look at a 5.56 or a 300blk case. Note the Diameter. Now look at a .308 case. note the diameter. Then think a bout the difference in surface area and friction, if you are a numbers guy you could calculate it. It is going to require more energy to remove the larger case with more surface area.
POF revolution, helps this process by using what they call E squared. They basically cut 4 flutes in the neck of the chamber so some of the residual gas helps with the extraction process. HkG91 uses flutes all the way through the chamber but is a roller locked system
On the surface this sounds like it makes sense but you're only talking about 'primary extraction' force to break the friction of the case sticking to the chamber.
After that the energy required to move the bolt and compress the spring is the largest consumer.
The gas port in a LR-308 rifle length gas system is about 0.096" and it has a MUCH larger/heavier bolt than the SFAR which has (by approximation) a 0.114" gas port. Actually the port in the barrel is likely larger but the #3 port in the SFAR regulator measures 0.114".
The port in the LR-308 rifle length system is about the same size as the average port size in an AR-15 rifle length system which ranges from 0.0935" to 0.098" ... source Tactical Machining.
Point being, I don't think it's valid to say the case being bigger is the only consideration in the balance of a gas system and the size of the gas port. There are other physics at work as well.
ETA: I have a barrel with flutes on my poodle shooter. It came from LaRue. I'm on the fence about the benefits over the aesthetics.
Last edited:
This is true and I had time to look up the size of the port. It's ShOcKINg.
The gas port in an unsuppressed carbine length 300BLK gas system is ~0.12" and suppressed it's ~0.105" (averaged).
By comparison a LR-308 with a carbine length gas system has a gas port ~0.635" for an 18" barrel and ~0.0725" port for a 16" barrel. Note, the port size is smaller for the longer barrel with the same gas system due to dwell time.
But for both the LR-308 barrels the port size for the "true" 308 is much smaller than the port size for the necked up 5.56 even though the case is bigger AND the bolt is bigger (probably the spring too) in the LR-308 than the 300BLK. I have to assume this is because of the enormous amount of gas available from the 308 compared to the 300BLK.
Based on this data from Tactical Machining it actually takes less of the available gas to cycle a LR-308 than a 300BLK even with all the case, bolt and spring differences. It stands to reason more gas is being delivered to the bolt in the "true" 308 with the smaller port but that doesn't mean the port has to be bigger to deliver more gas.
Last edited:
I should have quoted just this part, as that is what I was replying to.
Did you consider the venting of the bolt carrier is different than a standard AR carrier, allowing it to flow more volume when the rings begin to open the port, for the same sized piston in the carrier? The SFAR carrier does apper to have larger (BCG ports)vent holes, than a standard AR15 carrier. Just judging off pictures. Giving it the ability to over come the extra friction issue from more surface area at initial extraction which requires the larger barrel gas port than a normal AR15, but still having early opening/carrier speed/dwell( especially with a can) issues, especially with hot ammo.
Don't even want to get into comparing it to a full sized AR10 as the "physics" are completely different because the larger, heavier design.
Last edited:
That part was before I found size comparisons between gas ports on AR-15s, 300BLK and "full sized" AR-308.
All AR-308 references in this post are to the "full sized" LR-308 with a larger BCG
I didn't compare mine when it was here but interweb comparisons make it look like the SFAR BCG is about the same size and weight as a standard AR-15 BCG. It felt and looked that way to me but I didn't do a detailed comparison or weigh them.
The gas port on a rifle length AR-308 (even with a larger BCG) is about the same size as the gas port on a rifle length AR-15 so I'm not following the reasoning behind the notions that a AR-308 needs a bigger port to overcome the sticktion on bigger brass in a bigger chamber.
The gas port on a carbine length 300BLK is almost double the size of the gas port on a carbine length AR-308. The 300BLK brass is smaller in every dimension except neck diameter than AR-308 ... if bigger brass requires a bigger gas port to overcome sticktion then it doesn't make sense that the ASR-308 port is smaller than the 300BLK port. I mean the 300BLK brass is about the same size as as 5.56 brass and the 300BLK port is almost 33% bigger than the AR-15 port.
I'm not leaning into it needs a bigger gas port because it shoots a bigger boolit.
So far you haven't addressed gas volume in your calculations. 300BO has way less pressure at the port than 5.56 because of both a smaller powder charge and a way larger bore volume. It needs the giant port because there's less gas to work the action.
300 also uses faster burning powders than a 308.
My Spear LT in 300 blackout has a .0585 gas port. Seems fairly small but it's not a pistol-length gas system. It's longer but not sure what it would correspond to in the non-Sig world. It's a 9" barrel, not the 16". IMO, it's overgassed but it eats/cycles anything I throw at it.
It's a piston gun, can't compare that to a DI gun as far as apples to apples. Piston is closer to the port and has a different area within the cylinder. My Spear LT is a 5.56, was 16" and IIRC had a .052" port. Most carbine gas DI 16" rifles have a .0635" port.
Gotcha and makes sense. Didn't think about the piston being that close to the port vs. the DI.
