[Hobbyman2007]

Took the used RFB out for the first time yesterday. Had a hard time adjusting the gas seeing as I'm a new owner. Started at 40 clicks out ,shooting 147grain hirtenberger surplus . Gas adjustment ended up at 5 turns out. I'm not sure if that is the proper adjustment but the rifle would fail to eject, fail to cycle ,jam a round under the action until I got there.
I paid top dollar for the low shot count gun ,and it came with 8 magazines , I tried 3 of them ,two of which will be hitting the garbage. I'll be trying the thermold mags and the other three . Was thinking the magazines might be the issue with failure to cycle .
I have a lot of reading to do before I'm proficient with the rifle so far so good . I'll chalk up the failures as learning experience.

 

[ronmar]

Did you watch my video on gas adjust up in the FAQ thread(link to vid in #21 of the FAQ)? Way over or under gassed can cause issues with cycling. Bottom line, if you can open it 2 clicks(to 7?) and it won't lock open on an empty mag, then it is the correct setting for that ammo. I wouldn't write the mags off just yet. If it is at the correct gas setting and lubed properly(another video link in question 23 of the FAQ) I would try them again...

 

[Hobbyman2007]

Thanks Ronmar, I'll be going through the process again for both the gas setting and lube job . Nice work on the videos by the way.

 

[Hobbyman2007]

Much better today, I can't believe how accurate this rifle is with the cheap ammo. Went through the gas setting and was at 7 turns out with the 147 gr. fmj hirtenberger, 5 turns with the 150 grain federal blue box .

 

[gderf]

@Hobbyman2007

Are you really 7 and 5 "turns" out or 7 and 5 "clicks" out? Huge difference between the two.

 

[Hobbyman2007]

My bad , 5 and 7 clicks out.

 

[gderf]

My bad , 5 and 7 clicks out.

Just as a point of reference, my new RFB shipped set at B+7.

I am able to run it at B+13 with PRVI Partizan 308 145gr FMJ M80 Ball ammo.

 

[henshao]

Mine runs about 7 clicks from bottom generally speaking

 

[okstatefan]

I'm curious why there is such a big variation in gas settings? Mine is a fairly recent build according to serial number, purchased right around Christmas 2016. I think I'm running at B+21 for almost all ammo at the moment.

 

[gderf]

There seems to be some variation in the gas pistons being supplied. What does yours look like? Mine gun was built in January of 2017, and I bought it in early February.

The piston has one ring on it and It's set at B+13 for Prvi Partisan M80 ball ammo. The gun will not operate reliably at B+15.

 

[ronmar]

Piston, gashead and port machining and alignment, piston design, spring resistance, action drag, chamber resistance, ammo variations, and that is probably the short list. Huge number of variables involved.

The RFB is prettymuch in a class by itself using a precise gas adjustment with virtually no overtravel, instead of overgassing and absorbing the excess energy in overtravel and buffering. Any 2 given RFB's using the same gas setting is mere coincidence IMO...

 

[henshao]

Of all the possible factors, though, it seems like there are a bunch of different piston designs and everyone is using different ammo.

 

[BlakeHanson]

The RFB is prettymuch in a class by itself using a precise gas adjustment with virtually no overtravel, instead of overgassing and absorbing the excess energy in overtravel and buffering...

But, properly dialed-in, with a decent brake on it, it can be a real pleasure to shoot.
...especially given the fact that it is throwing some serious lead, not 22's.

 

[Hobbyman2007]

Confirmed then reconfirmed , 7 clicks out . This again is with hirtenberger 146 gr. I love the way it shoots in comparison to my overly heavy m305 norinco. Because this is a Canadian version at 18.5 " of barrel I don't have any threading for a muzzle break . I'm still recouping from the purchase ,so don't have the mad money to have a gunsmith thread the barrel. From what I've read the "clamp on " brakes work but are a little dangerous . Any opinions or users of the clamp on what to add their two cents I'm all ears .