If the barrel drops open easily and has any side to side movement when opened, the need for a larger pin is indicated. That "play" at the hinge does not miraculously go away when the barrel is closed and permits the barrel to move in an inconsistent manner while the bullet is traveling through it. This opens groups. To reach a barrel's accuracy potential, this play at the hinge must be removed.
In our bolt action rifles, we go to great pains glass bedding receivers and either floating the barrel or applying a controlled pressure to it to improve shot to shot repeatability, aka accuracy. And with all the custom gunsmith's attention to metal details, the last thing we would accept in a high dollar custom rifle, or any conventional rifle or bolt action handgun for that matter, is a barrel that is loose in the receiver. So why accept a loose barrel in a break open gun like the Encore? In today's jargon, "It's a no brainer," yet this obvious concept escapes too many shooters.
Continuing this logic, we pay higher and higher prices for barrels and custom forend bedding systems in pursuit of accuracy. Doesn't it stand to reason that this investment is seriously undermined by a barrel that shakes and rattles while the bullet is traveling through it?
The benefits of a
tightly fitted hinge area
have been proven
over and over in thousands of Contenders using my Contender Oversize Hinge Pins
for over fifteen years. With the Contender, one size pretty well fits all,
but with the Encore the larger hinge pin holes vary by at least .003" in both
factory and custom barrels, thus making it necessary to have a wider range of
pin sizes available. To this end, I have had a special run of larger pins
made matched with appropriate reamers to give the degree of fit needed for
achieving top accuracy potentials from any custom or factory Encore barrel.
Which pin is the right size?
The "standard" oversize pin is about .0005" or 1/2 of one thousandth inch larger than most factory issue hinge pins. They improve the fit, but in many instances are not large enough for a really precise fit, which should be in machinist's terms, an "interference fit." This is the kind of fit we are after.
An interference fit requires the Well Lubed parts to be forced together, whether by pressing them together or by some degree of tapping with a hammer. An interference fit in a machined hole with a coarse inside surface finish is merely burnishing down the tops of the rough finish and should never gall or cause the parts to seize. Anything short of this is desireable.
The "Standard" or 1x oversize pin.
Virtually all Encore barrels and frames readily accept the "Standard" or 1x oversize pin. But some holes in a barrel and frame combination may not accept the next size larger pin without reaming. Testing the individual holes with the 1x pin will give an idea of the relative size differences between the holes and the pin. If the 1x pin passes through a given hole freely or with very little tapping, then the next step larger pin, the 2x, will fit.
Try the 2x pin by tapping it into each of the three holes with the barrel off the frame. Note that it is just over approximately 1/2 thousandth inch larger than the 1x pin. If the 2x pin is simply too tight in a given hole, then that hole should be reamed.
For the 3x oversize pin, follow the same logic, bearing in mind that larger holes may also require any future barrel & frame combinations to be reamed to the larger size also, and this may not be something you want to do.
For example, I have an Encore frame with a .440" hinge pin hole diameter that I use only for test firing for chamber size and finish. Accuracy from this frame is not a factor to me. If it were, it would be best to send it to TC requesting a replacement. I thought about making pins larger than .4393," but decided that the associated reaming to a still larger size would cause problems with fitting when those barrels or frames were used with opposing parts not reamed. Thus, .4393" is the largest I intend to produce at this time, though for special applications, .440" or larger is a possible option. Ask if you find you need larger pins. Small quantities are expensive to do, but I may be able to help.
Always lube and install the issue pin first to line up the 3 holes as you tap in the larger pin.
Oversize Hinge Pin Reamers.
Adjustable, Expansion Reamer.
This allows adjusting the hole or holes to the degree of fit desired. However, the expansion reamer does require more attention to detail and care and caution in its use. Evaluate your own aptitude with hand tools, and govern yourself accordingly. Remember, normally you will be removing only a few ten thousandths from the inside of the hole, except where there are more extreme differences, but even then you will only be removing at most a couple thousandths.
In use, the expansion reamer is adjusted so that it slips into the hole. The adjusting screw in the end of the reamer is turned until there is slight resistance to turning the reamer by hand. Then in very small increments, the screw is turned in until light shavings of steel are removed from inside the hole when the reamer is driven with a wrench on the square shank of the reamer. The hole is then tried for fit with the appropriate pin, and the reamer adjusted to take out more material as needed.
Done carefully, the barrel and frame can be reamed together, but any angular misalignment of the holes can wallow the holes.
The expansion reamer is the best method of reaming the holes, and it is adjustable throughout the range of sizes you will need for fitting any of the oversize pins. It permits obtaining the precise degree of fit wanted, from just short of galling to moving freely. If the fit is tighter than you want, just tweak a few more shavings from the holes.
"Chucking Reamers"
Using these special size chucking reamers is more straight forward. They come with a "star" handle installed for hand held use and the .438" and .439" sizes are appropriate for the desired .0003" "interference fit" with the specially ground .4383" or .4393" pins.
Because these reamers also cut on the lead end, never attempt to ream all three holes at once.
Any misalignment of the holes will result in the
lead end cutting that misalignment into the barrel hinge pin hole also. I have "sleeved " barrel hinge pin holes ruined when this was attempted on Contenders, and while it can also be done to save an Encore barrel, why risk it and incur the unnecessary expense. Repeating, NEVER ATTEMPT TO REAM THE THREE HOLES WITH THE BARREL INSTALLED IN THE FRAME USING A CHUCKING REAMER.
As the chucking reamer enters the hole, there will be some flaring of the hole due to the inherent misalignment of the hand held reamer with the hole. But as the reamer enters the hole, the "radial lands" behind the cutting edges of the reamer will guide it. GENTLE is the order of the day. Use light pressure as you turn the reamer.
Be sure to examine the insides of the holes after reaming, but don't be too surprised to see much of the original finish untouched by the reamer. You are only knocking off the tops of the rough finish inside the hole, taking out the last few tenths of a thousandth needed to match up the holes for a beautiful precision fit. (Likewise using the expansion reamer.)
IMPORTANT WARNING:
Since I have no control over how you use these tools, I assume NO liability for the results you obtain. The procedures are pretty straight forward, and I am confident anyone can achieve good results using them, but if you "blow it," you alone are responsible for any loss or expenses you incur. That said, I offer:
I am not an FFL holder so YOU CANNOT SHIP FRAMES TO ME. All work involving frames is done at my dealer's place of business. Contact me for details, or see also the Encore section of my "Trigger Jobs" webpage for instructions for shipping to:
Bradbury Gun and Tackle
1809 Rogue River Hwy
Grants Pass, OR 97527
phone: (541) 479-1531
Shipping Information:
Handguns cannot be sent through the postal system, except, as I understand it, from dealer to dealer. It is best to ship handguns via UPS or Fed Ex, both of which require handguns to go via next day air. Long guns can be shipped by ground through both the postal system, UPS, and Fed Ex.
You as an individual can send your firearm, technically the serial numbered part, the frame, to a licensed dealer (FFL holder), and he may return it directly to you. You do not need to go through a dealer if it is a long gun or if it is a handgun being shipped via UPS or a dealer if it is a long gun or if it is a handgun being shipped via UPS or Fed Ex.