.

Robin

Robin

.577 Tyrannosaur.
Messages
20,319
Reaction score
43,997
Location
Livingston County
With no forward assist, How do you seat the cartridge if, for any number of reasons, it fails to achieve battery?
That VLTOR looks like a good beefy piece of equipment, so I must be missing the obvious.
Robin
 
B

BDSKJCHRIS

.40 S&W
Messages
137
Reaction score
73
Location
capital region
Robin said:
With no forward assist, How do you seat the cartridge if, for any number of reasons, it fails to achieve battery?
That VLTOR looks like a good beefy piece of equipment, so I must be missing the obvious.
Robin
Click to expand...

put your finger in the indented portion of the bolt carrier (where the gas vent holes are) and push it forward. if that doesn't work you either have an out of spec round or a chamber obstruction, in which case pull the charging handle and get the bad round out of there.
 
Podmonkey

Podmonkey

.577 Tyrannosaur.
U.S. Military
Messages
21,592
Reaction score
30,177
Location
Cambria co. PA
BDSKJCHRIS said:
put your finger in the indented portion of the bolt carrier (where the gas vent holes are) and push it forward. if that doesn't work you either have an out of spec round or a chamber obstruction, in which case pull the charging handle and get the bad round out of there.
Click to expand...

Not fun to do after you've fired it for a while.
 
meketrefe

meketrefe

.450/400 Nitro Ex
Messages
12,806
Reaction score
16,327
Location
Dexter, ME
Hix
There is nothing in any upper that will make it stiffer no matter how much one spends. A tighter fit perhaps and matched billets are the way to achieve that but relstive to the tenon they all the same dimensions in that critical area. Only monilitic uppers releave the stress from the barrel nut when they are pushed down but one could also couple the handguard with the upper using a coupler or a shallow mount so it will not interfere with the scope and mount.
These are the only two ways to releave stress in the weakest part of the upper. One expensive the other not so much. Brands do not matter a thing here.
The forward assist is like everything, you can have it and not need it or need it but dont have it.
Stag, lar, mega have left hand receivers or at least they used to. Arp makes the best bolts including left hand.
The bullet guy is and awesome guy and he will hook you up.
 
meketrefe

meketrefe

.450/400 Nitro Ex
Messages
12,806
Reaction score
16,327
Location
Dexter, ME
Skeet_Man said:
Meke- Thanks for the info.

Unfortunately a standard LH upper is a no-go on the SCR since you can't use the corresponding LH BCG (SCR has a proprietary bolt carrier). On a RH BCG when the gun is in battery, the cam pin cams to the left, and on a LH BCG the pin cams to the right. The SCRs pin cams to the left (for RH use), with no ability to get one that works the other way without fabricating one from scratch.

DPMS actually made a LH upper that used the RH carrier and a special LH bolt head, which would work fine w/ the SCR, and that was my initial plan. Problem is that the gas vent holes in the BCG end up venting into the solid wall of the upper, and then back into the upper and lower. I figured venting the gas directly back into the action was not a recipe for success in the long run. Only other option would be to put setscrews in the RH vent holes, and drill new vent holes on the LH side but I don't envy the proposition of trying to drill and tap 8-32 or 10-32 holes into a hardened bolt carrier. I'm actually pretty bummed I won't be able to use the DMPS upper, that would be been absolutely perfect for what I want, I just don't want issues down the line due to all the crud the carrier will be dumping back into the guts of the gun. The only other viable option would be to convert the gun to piston, which gets rid of the gas venting issue, but I'm well past the point of diminishing returns then.

The LH upper linked is actually made w/ the DPMS LH upper I mentioned before, JSE must be assembling them in house.
Click to expand...

Oh! Ok. I am not familiar with scr. Personally I see no reason for not using standard AR parts and equipment.
If compliance is needed the FRS stock works beautifully.
In any case the bridge will help you with any sort of upper given you have a top rail that you band bridge.
That is the the weakest spot of the AR15 upper receiver no matter what brand or upper.
Never try to bind both by running over with the optics mount or rings. If one binds them with a coupler then make sure
they do not touch the scope or mount. Some can be found inexpensively in ebay, amazon, gunbroker. Or one could take
a 45 degree offset and cut it from the top so it is very shallow and ends up being 15 bucks for much added rigidity.
If one has a tube one could order a machined section to raise a section of picatiny rail and then bind it that way.
POF makes top rails that are bind but I think only work with their handguards.
 
You must log in or register to reply here.
Top