View Full Version : Timing question
March 16, 2012, 09:51 PM
I am no pistolero supreme, so forgive my ignorance.
I understand that to check the timing on a wheelie, one pulls the hammer back and checks to see if the cylinder can be moved to the point of "clicking."
Correct so far?
If that is the case, how does one check the timing of a "hammerless" design?
March 16, 2012, 10:58 PM
Simply by pulling the trigger slowly, listening and watching.
March 17, 2012, 09:39 AM
On a double action revolver, with the thumb and index finger of your left hand holding the cylinder with slight pressure as to keep it from moving, pull the trigger with your right index finger very slowly as you watch for the locking bolt to engage the locking notch in the cylinder. The bolt should "drop" into the notch just before the hammer falls (with that slight pressure restricting the turning of the cylinder).
March 17, 2012, 11:41 AM
Thank you very much
March 17, 2012, 02:26 PM
S&W revolver armorers are told to check the "timing" (carry up) in the New Model DAO 5-shot revolvers using DUMMY rounds in the charge holes.
This is because the cylinders lack the older (and breakable) cylinder pins to hold the extractor. The ammunition cases (DUMMY rounds for bench checks) provide the pressure to hold the extractor properly positioned in the cylinder. (After all, the extractor is cut with dummy rounds in the charge holes so the ratchets are positioned to provide proper carry up with cases in the charge holes.)
With the cylinder charge holes filled with DUMMY rounds, and NO pressure is being applied to the cylinder (in other words, don't touch or create any drag on the cylinder), the trigger is slowly pulled to the rear. Slowly ... not slooooooowwwwly.
If you're holding the gun with your right hand, and pulling the trigger with your right index finger, then your left hand can hold the barrel to stabilize the gun during the slow trigger pull ... not the cylinder.
The cylinder stop's ball should engage each cylinder stop notch before the hammer falls.
Repairing a "does not carry up" condition (or, a "timing problem", if you'd rather) has a couple of possible corrections.
The hand can be replaced with the next larger (oversize) hand available for that model. Oversize hands can vary, and sometimes using a micrometer to identify the next closest size to the original one is handy.
The use of an oversize hand, however, might also create a condition known as a "long ratchet". That condition can be repaired (file, knowledge & some experience).
If the larger hand doesn't correct the DA carry up, then the extractor will have to be replaced. S&W makes a cutting hand/arm for that purpose, which is sold to revolver armorers (a lever bar welded to a trigger, into which is installed a cutting hand - to cut the steel ratchets - and which replaces the actual trigger for the purpose of cutting each ratchet in the specific revolver model). Obviously, this is a repair best left to the factory repair techs, or a gunsmith (or trained armorer) who has the proper tools.
Cutting a new extractor is always done using the original stock hand, BTW.
Also, the use of an oversize hand which is too wide can create binding, and get you into territory where the frame's hand window might require adjustment ... which means you may risk damaging the EXPENSIVE frame (serial numbered part of the gun). :eek:
Sometimes proper cleaning of a revolver can "restore" proper function, though, so it might be a good idea to have the gun examined by a gunsmith, to make sure a "repair" isn't needed (but just a good cleaning & lubrication).
Now, pulling back on the trigger and checking to see if the cylinder can turn and produce "clicking" is another test (known as checking "hand sing"), and it can be done with pressure to different parts/sides of the trigger ... but it's also not something that is probably easily understood, done (or addressed) by the average revolver owner.
Got a good gunsmith nearby who can help you inspect/check whatever revolver it is you're wondering about?
March 17, 2012, 05:04 PM
I had not considered this aspect of revolver functioning before reading your explanation above.
Here is my question: Does cycling a revolver without cartridges in the chambers (charge holes) put more wear on the ratchet and extractor in relation to the cylinder (because the extractor isn't held in position/alignment as securely)?
March 17, 2012, 07:18 PM
We weren't given any warning about dry-firing without snap caps. We did a lot of dry-fire during the armorer class, too.
I just mentioned it because the extractors in the new style revolvers (without extractor pins) rely upon the ammo cases to position them to optimal advantage for consistent engagement of the hand with each ratchet. (Unlike the old style extractors which were held in position by cylinder pins ... which could become damaged or broken at the most inopportune times.)
The presence of the cases in each charge hole helps eliminate any tolerance "slop" between the cylinder and the extractor, too.
When we were practicing cutting new extractors in the armorer class we didn't have any dummy rounds, and virtually all of the extractors being cut still exhibited good fit & carry up when the guns were checked without the use of dummy rounds. I'd always use dummy rounds (or empty cases) when cutting an extractor for a "real" revolver, though, meaning outside the class. ;)
Also, when a new style revolver is being checked "for real", it's recommended to use the dummy rounds so the most accurate observation of the gun's carry up can be observed & checked.
March 18, 2012, 08:16 AM
Thank you for the clarification, fastbolt.
March 18, 2012, 08:24 AM
This is because the cylinders lack the older (and breakable) cylinder pins to hold the extractor. The ammunition cases (DUMMY rounds for bench checks) provide the pressure to hold the extractor properly positioned in the cylinder. (After all, the extractor is cut with dummy rounds in the charge holes so the ratchets are positioned to provide proper carry up with cases in the charge holes.)http://emoticoner.com/files/emoticons/smileys/gold-star-smiley.gif?1292867608Good information. It makes perfect sense, but I'd never considered it before.
March 18, 2012, 09:37 PM
"After all, the extractor is cut with dummy rounds in the charge holes..."
That may be done in some armorers class but I beg leave to doubt it is done that way at the factory. If you look at the extractor and the way it is made, you will see that pins or not, dummy rounds or not, it is impossible for the extractor to become mis-aligned with the chambers. (Look at the points of the "star" and how they mate with the cuts in the cylinder.)
I will also note that it is quite common for older S&Ws not to time up fully when the cylinder is held back and it is very common for older Colts not to come up all the way until the trigger is pulled. The real test is if the firing pin strikes the primer in its center every time. If it does, any slop under abnormal conditions is not important; if it does not, that revolver needs work.
December 30, 2012, 06:43 AM
The search function turned up this thread when I asked for info about timing problem with an old gun that I have.
The gun itself is an antique Belgian Bulldog chambered for the .44 Webley/.44 Bulldog.
When the trigger is pulled, either SA or DA, the cylinder advances but not all the way. It stops about 20-25% short of full alignment of cylinder and forcing cone. If I give a gentle push to the cylinder, it slides into alignment.
This problem is uniform for all five chambers in the cylinder.
It seems to me that the hand is not pushing the cylinder far enough. I have yet to take the little gun apart and clean and polish the interior - don't like to mess with antiques more than necessary. If cleaning the gun does not solve the problem, is it possible to lengthen the hand by peening it carefully?
PS - already checked Numrich Arms....no hands available.
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