tc encore prohunter 3x oversize hinge pin 3x hp
This is the next size up from the 2x Bellm Encore Oversize Hinge Pin system. It is the one to order after you determine the 2x pin is not large enough to give the degree of fit you want.
At .4383" diameter, you will find that many barrel or frame hinge pin holes must be reamed for the 3x Bellm Encore Oversize Hinge Pin. Refer to the Tools menu option for reamers.Note that the factory cannot hold hinge pin hole tolerances to less than .440," but if you ream a hinge pin hole to .4393" they may want to void their warranty for those components that have been reamed. Thus, you should give serious consideration to reaming holes.Don't be surprised if in some holes the .4393" 3x pin is still not big enough. In addition to my shop frame, I have run across several others so far with frame holes at least .440" in diameter.Note that the 2x, 3x and 4x pins are limited production, specialty items, thus the higher price compared to the 1x pins. But even at $15 each, they are cheap compared to the time and money wasted trying to make a problem barrel shoot in the first place or taking a loss selling it when you can't make it shoot. OK, no time shooting is wasted, I agree. But if you are going to shoot, then shouldn't you be getting the best you can from the investment you have made?
If your barrel drops open easily and has any side to side movement when opened, that "play" at the hinge does not go away when the barrel is closed, and it permits the barrel to move in an inconsistent manner while the bullet is traveling through it. To reach a barrels accuracy potential, this play at the hinge area must be removed. Stop wasting ammo trying to get your barrel to shoot, just oversize the hinge pin.
The hinge pin holes in Encore barrels and frames vary much more than the holes in Contenders, so much so that in some instances the hinge pin must be at least .003" larger than "stock" in order to get the same degree of precision fit common to the Bellm Oversize Contender Hinge Pins. Stainless steel frames are prone to accept the 3x pin, a result of galling and/or lack of lubrication.
Reaming for these 3x pins is sometimes necessary but with our quality hinge pins often avoidable. The 1x at .4377" and 2x at .438" and now the 3x at .4383", they fit most all factory and custom barrel hinge pin holes. Testing the fit of the 1x pin then the 2x pin in each hole gives an indication as to whether the next larger 3x pin is needed to get the optimum fit desired, that of a bank vault door opening and closing. I know, you never had the privilege, but you get the idea. It does not shake and rattle all over the place.
Use the 1x pin then the 2x pin as a gauge pin to determine if you need this 3x pin. Simply lubricate the hinge pin, frame and barrel hole with a common cutting/tapping or heavy viscosity oil. Center the hinge pin on a given hole checking for axial play and resistance. If it is not tight enough, consider it as a gauging tool to determine if a larger pin is called for. When installing the oversized hinge pin, always install the stock hinge pin first, then tap out of the way with the oversized pin. Always remember the lube.
Taking accurate measurements of pins and holes is common among machinists, but not in the realm most folks are familiar with. Thus, the best solution I have found to bridge this technology gap is to simply use a process of elimination by going from one size pin to the next. Anyone can tell if a pin is loose or tight, right? The Encore hinge pin system is a well proven system. "Trial and error" is working very well, and groups are tightening. That is what counts.
So, start with the 1x pin then the 2x unless you have a means of accurately measuring your hinge pin holes in your barrels and frames. By the way, calipers are not accurate enough to give more than a rough idea. Trying a pin is still the best method available to most shooters.