the actual skinny on the RWB oprods is as follows:
they are dimensionally and metaleurgically equivalent to the original USGI parts.
One piece forged like the the TRW's and milspec black parkerized.
they are NOT a drop in part and require correct fitting to the chosen receiver.
they are NOT over sized at the tab...... I say this as several guys have bought them and followed advice posted by laz2000 in his how to fit an oprod thread of several months back..... and have buggered up thier new parts by filing the tab.
it is the bearing surface above the tab that must be fitted to your receiver. the tab itself, in most cases, simply needs a polish to break the parkerizing.
regardless, I have installed over 40 now for custom builds and installs to stock norinco rifles and probably have more experience with these oprods than anyone in the country.
What can they do for your rifle?
any semi auto rifle's potential accuracy can only be realized once negetive vibrations and sloppy fitting parts have been dealt with. The RWB or any new, to usgi spec oprod, allows for a custom fit to your action and if installed correctly should have no up and down play that is very common with the chinese oprod.
a tighter fitting oprod, with no up and down play in the receiver track lends itself to accuracy as the oprod now travels in a tight path, giving the same stoke every time. This is also of benefit to the rifle's other parts as there is less wear possible to the bolt roller, gas piston, oprod guide and the receiver itself.
On many rifles i have built using these oprods, what you end up with is a hydraulic like smooth feel to the oprod when manually cycled, with no play or wiggle whatsover.
Are they an instant accuracy improvement...... NO, but a tight oprod is definately a building block to reach your particular rifle's potential accuracy.
for guys building from the receiver up, or for those simply wanting a much better fitting part, the RWB oprods are an excellent choice.
I also have these oprods in stock , and am selling at the same price as Dlask and I also offer correct installs