Which one do you think has more braking power on cylinder inertia, the bolt nose on a large circle/orbit or the hand nose on a little circle/orbit?Ok, first, you're describing either a hand that is too long or an excessive reset cut or a combination of both. You have to know the "how" to figure out the "what it is". When setting up timing in a Colt type action, the first step is to have a correct length hand (thought I was going to say Arbor right?!!! Lol). The "givens" you have is the hammer selected and the trigger selected.
The hand is installed on the hammer of course and it will rotate the cylinder and bring a chamber to battery. So, the hand length is correct when the bolt locking the cylinder and the trigger sear reaching the full cock notch happen simultaneously (one should drag a finger on the cyl when checking this). That is the " length of cycle" in which all cycling operations have to happen. Over rotation of the hammer to get to lockup means a short hand, lockup before full cock means a too long hand.
After achieving the correct hand length, you can then adjust the bolt drop which means "when" the left bolt arm will fall off the cam allowing the bolt head to contact the cyl surface. This should happen a bolt width to 1 1/2 bolt widths before the locking notch (with or without an "approach" (lead as some call it)). Achieving that, you should have 3 distinct "clicks" - half cock, bolt drop, and full cock (including the simultaneous bolt locking the cyl ). That is correct timing.
The described "premature" turning of the cylinder can now be deciphered. If the timing is correct, then the reset cut is the problem. This is the area on the bolt arm where the cam fits with the action at rest. When the cycle is started, the bolt should almost immediately be "picked up" (bolt pickup) by the cam which will unlock the cylinder. If the cut (on the arm) has too much clearance, pickup will be late and the hand will be trying to turn a still locked cyl.
So that's how you determine if it's a "hand thing" or "bolt arm thing".
The bolt should only have about 4 lbs pressure (not a lot) so even though there's obviously contact with the cyl, the drag from the bolt head is pretty minimal. The main " braking" of the cyl is (by design) the hand. As the hand rises during the cycle (its contact with the ratchet is vertical) the hand spring tension is increased by the increasing angle of the hand slot (chimney). This increase in tension retards the rotation of the cylinder by the hand's contact of the up coming ratchet tooth and conditions the cyl for lockup. One of the first signs of a weakened or cracked hand spring is cylinder throw-by (over rotation).
Lastly, the bolt window in the frame is too large for my tolerances (allowing excess horizontal bolt movement) which is exactly why I install a bolt block in every S.A. I tune. It's one of the best passive installs one can do (the other being an action stop). It supports the bolt horizontally during lockup while allowing it to move freely to lock / unlock the cylinder. It also increases the mechanical accuracy of the action, protects the bolt and the cylinder locking notches from side to side wear. It allows you to "treat um like a Mule!"!!
From experience, heavy bolt springs do more harm and aren't needed especially since you have the hand to do the job it was intended to do. It's not my design, . . . most folks don't know the hand has two jobs. First is carry up and second is braking.That is so funny! Who in New Yourk or Chicago pays any attention to gun laws? Oh right , honest citizens, the real outlaws that need watching !
Which one do you think has more braking power on cylinder inertia, the bolt nose on a large circle/orbit or the hand nose on a little circle/orbit?
From experience, heavy bolt springs do more harm and aren't needed especially since you have the hand to do the job it was intende
You're right, you still don't get it! Lol
d to do. It's not my design, . . . most folks don't know the hand has two jobs. First is carry up and second is braking.
I know with a weak or broken hand spring, you will have throw-by so . . .
I was taught the design and that's what I practice. I may use different springing but all the parts still do what they were designed to do.
Oh, I get it, I just think your wrong about short arbors, accuracy and a tendency to blow the barrels off !You're right, you still don't get it! Lol
Ok, you mean me, Colt, Larson Pettifogger, Pietta, Long Hunter's . . . with a little mechanical engineering tossed in . . .Oh, I get it, I just think your wrong about short arbors, accuracy and a tendency to blow the barrels off !
Oh, I get it, I just think your wrong about short arbors, accuracy and a tendency to blow the barrels off !
Talk to me brother. What 10 things do you consider essential ahead of arbor fit? If i buy anything other than a Pietta, the first thing i correct is arbor length and wedge fit. I want the wedge thumb pressed in, not driven in.
This gun gave me the only chainfires I’ve ever experienced. Pietta said the chambers were reamed to 456 and I loaded it with 457 balls. Caboom! Pin gauges say it’s closer to .4565” so it got a steady diet of.457 conical or .465” round ball. Very accurate pistol."I don’t ream them myself and again, only if needed. I send them out to Charlie Hahn for this, he cuts them to .456”, does an excellent job and doesn’t cost much."
Charlie bought that reamer to do a cylinder for me quite a number of years ago. A .456" chamber will hold a .457" ball securely, no creep, at least with 25 grain loads. At the price he charges it's not worth doing it myself.
"Usually recut the cone to 11 degrees."
+1 on that!
Amen, I have found the same things to be true in my own work and experimentation on open top revolvers! Fixing a short arbor is easy enough to do and harms nothing but is really a solution in search of a theorized problem ! I'm quite sure Pietta engineers realized this at the get go from the accuracy , longevity and safety stand point but since getting re-equipped with CNC driven machinery it made it easy to fit up the short arbors without expensive hand fitting which would have jacked up their costs before CNC implementation.Sorry for the delay in responding Lee… been down with bronchitis and sinusitis since Memorial Day. Back in the saddle again!
That was a wise guy comment on my part Lee (Surprise surprise.) as the first six priorities are the chambers. I use a set of pin gauges to check dimensions and concentricity. New guns get looked at this way stripped and filled with mobil One grease or equal and then I shoot them. Even an out of spec revolver can shoot surprisingly good groups. If so, I leave it and just move on to sighting in.
I don’t think I own more than one or two guns with stock chambers unless you count Ruger Old Army or Pietta Shooters Models as they’re usually accurately cut and sized appropriate to the bore dimensions. But I haven’t seen a replica with proper chamber/bore dimensions. I don’t ream them myself and again, only if needed. I send them out to Charlie Hahn for this, he cuts them to .456”, does an excellent job and doesn’t cost much.
Check the barrel extension and forcing cone. Check for square and face and recut as needed. Usually recut the cone to 11 degrees. I also check the muzzle and if it’s square and clean, leave it alone, otherwise square and crown.
That the revolver is properly timed.
That the trigger breaks crisp and clean at two and a half pounds or so. I don’t like them much lighter for an everyday gun and not heavier than 3 pounds.
That the bore doesn’t have tight spots anywhere (mostly applied to Remington, R&S, and Rugers) although a choked bore in the final inch or so isn’t so bad.. Is that ten items?
Regardless. Once that stuff is addressed I may or may not shim the arbor. On pistols which may have collectors value down the road I don’t mess with it. I have addressed the arbor fit on maybe 8 or 9 guns so far and it really hasn’t made any functional difference for me except that when I assemble those revolvers I don’t consider setting the end shake with the wedge as I always had previously. I just tap the wedge into place by feel and she’s good to go.
The last thing I do with any gun is sight it in… all Colt 1860’s, probably all open top replicas, shoot high, some really high. (I’ve used peacemaker front sights before, looks weird but shoots grea.) I’ve made sights of brass stock but I also have a film can full of the Colt Open Top from sights from Uberti. Taller than the 1860 sight and combined with some file work on the hammer it’s usually all that’s needed to get to point of aim at 25 yards. Heck of a lot easier than making it from stock. Vti gun parts has them, part number UB900015 for a bit under ten bucks.
I know, I know, I’ve been told so many times and in so many ways how critical it is and that my guns are being slowly destroyed, aren’t as accurate as they could be, Sam Colt wouldn’t have had it, and so on and so forth. The thing is, I’ve been shooting short arbored replicas since 1960. And there have been years when I shot daily. I’ve replaced wedges, hands, bolts, cams and so on. They do wear out. In fact wedge wear was one of if not the principal complaint directed at the design by the government. But my oldest replica, also my favorite, is now 60 years old and has been fired with full power loads behind mostly conical bullets and it’s as accurate and reliable as the day I received it.
One of the things I have found in regards to factory wedges is that several I have dealt with were to soft and over time developed low spots that peen up either side and thicken it at these points where they compressed against the slots. When these low spots with the edge peen get deep enough it does two things, 1. It increases cylinder/barrel gap and this in turn makes the muzzle tip downward a bit ( altered lower lug fit) at ignition lowering point of impact.Amen, I have found the same things to be true in my own work and experimentation on open top revolvers! Fixing a short arbor is easy enough to do and harms nothing but is really a solution in search of a theorized problem ! I'm quite sure Pietta engineers realized this at the get go from the accuracy , longevity and safety stand point but since getting re-equipped with CNC driven machinery it made it easy to fit up the short arbors without expensive hand fitting which would have jacked up their costs before CNC implementation.
I also believe from what I have seen to this point that harmonics (particularly in open frame guns that were designed with flex in mind ) is a great theory that has no provable deficit to accuracy or strength issues. Ransom rest testing may change my thinking on this but I have to say what I believe to be true at this point in time of personal usage and discovery.
End of arbor joint compression via the wedge and slot seats creates no more resistance to barrel expulsion than if there is a gap. Harmonics plays no part in adding or detracting from strength in this instance. It is a pure (slot/ wedge) fit, tensile , ductile and compressive strength of steel issue here. All of the resistance pressure is on the key and end slot of the arbor. The end of the arbor well (which is part of and one piece with the barrel) is (at ignition) always and for ever trying to move away from the end of the arbor and drag the wedge and end of arbor slot with it.
I have never personally witnessed any Pietta reproduction. of any model , that has been proven to have blown off the barrel because of a short arbor. It has happened from arbors which were altered from factory spec.
Enter your email address to join:
Register today and take advantage of membership benefits.
Enter your email address to join: