Revolvers/ barrels/forcing cones

First topic message reminder :

This gun does not shoot well.. Inspection reveals a very poor forcing cone.. Forcing cones are poor when cut with some degree of precision.. This one has very little if any precision involved.. The bullet shows the point of engagement with the rifling.. See how much of the projectile is completely unsupported..Still in limbo between the cylinder and the bore.  Wonder why revolvers lead excessively.. ?? There's a clue..The last picture shows the barrel zeroed in the spider, and the Taylor Throat reamer doing it's job..more to follow...   

john bickar wrote:I feel like a Marksman must feel when squadded next to a High Master.

I don't even know what I don't know about what's going on here.

Wowsers. Thanks for sharing your craft, Jerry. Your photos are meticulous.

Same boat!!  Just soaking it in and learning!!!

Traditional forcing cone-itis...

Crowns

The first picture shows a  "Salad Bowl" shaped  recessed crown.   I don't believe this shape contributes to accuracy.  The gases are not free to escape without deflection back onto, and into the path of the bullet .
I cut an angle to remove the bowl shape and allow the gases a straight exit.  2nd pic..

Would like to open this topic again..just bought a Taurus Tracker 38/357 revolver and dropped in my Brownells forcing cone "go-no go" gauge.  The gauge drops considerably down in the Taurus, included a pic of the gauge in as well in a very used S&W 686. Haven't shot it yet to check for accuracy...but any opinions related to the Taurus forcing cone?

quality control at its finest. That’s the no-go?
Never mind, send the picture to Taurus!

It's the latest in Taylor throating LOL
Jon

Lol

Sent the pics to Taurus, BTW also pointed out the cylinder/barrel gap varies from .003 to .005 (with cleaned extractor and cyl face). This is their response (wording as rec'd):

Have you been able to shoot the firearm? Sending the firearm in is your decision but all of the numbers you have provided is with out company specs and they're with our tolerance. I highly recommend shooting the firearm and seeing how the firearm shoots before sending it in. We do have a 12 week turnaround. If you decide sending the firearm in is something you would like to do I will be happy to assist you. 


If the gun meets their specs..why send it back?  I have never seen a beat up 357 with a throat that large.  I intended to shoot a lot of 38 HBWC, am I correct seeing bullet base separation from too large of a forcing cone throat in the past?


FYI: The gun is new in box never fired.

Hmm I wouldn’t think passing a no go would be in specs but they must have something different.

Show it to your dealer/gunsmith

This is why I will rarely get on a forum member for dredging up old threads.  The after picture of the reamed barrel, and the newly crowned muzzle wake up something primitive in me. Very, very nice.

Upper40 wrote:Sent the pics to Taurus, BTW also pointed out the cylinder/barrel gap varies from .003 to .005 (with cleaned extractor and cyl face). This is their response (wording as rec'd):

Have you been able to shoot the firearm? Sending the firearm in is your decision but all of the numbers you have provided is with out company specs and they're with our tolerance. I highly recommend shooting the firearm and seeing how the firearm shoots before sending it in. We do have a 12 week turnaround. If you decide sending the firearm in is something you would like to do I will be happy to assist you. 


If the gun meets their specs..why send it back?  I have never seen a beat up 357 with a throat that large.  I intended to shoot a lot of 38 HBWC, am I correct seeing bullet base separation from too large of a forcing cone throat in the past?


FYI: The gun is new in box never fired.

The problem you’re gonna face is Taurus probably has a different go/no-go gauge for the forcing cone. There is Not a firearms industry accept standard on dimensions other than what’s in the SAAMI or CIP standards for cartridges and chambers. So long as there’s no safety issue manufacturers are free to adopt whatever tolerances and clearances they like. So, I suggest shooting it and seeing how well it shoots. It might surprise you. Whether or not a HBWC will separate will need to be tested, but I doubt it.

Does the Taurus cone have a gradual slow taper or is it sharp and abrupt like the Smith's typically are?
Jon

Jon Eulette wrote:Does the Taurus cone have a gradual slow taper or is it sharp and abrupt like the Smith's typically are?
Jon

It looks like a long taper...tried to get a couple of pics.

Rough as a cob.  What on earth do these guys use for machine tools???

Probably a bunch of these.

https://www.tramarindustries.com/listing/1995-nardini-fast-trace-cnc-teach-lathe/

The consensus is that they’re decent for the price point. The electrics could be better perhaps, but for production use they hold up well.

It is a great looking gun, finish is great, timing and lock-up spot on. Was considering using it next year for action pistol..always liked the underdog. Guess I just need to get out there and see what I can do at 50 yards.

Great info. Now the question is who would I send my 14-2 to for that quality of work?

estuck wrote:Great info. Now the question is who would I send my 14-2 to for that quality of work?

Search Google for Gunsmiths Brazil

Jerry Keefer wrote:This gun does not shoot well.. Inspection reveals a very poor forcing cone.. Forcing cones are poor when cut with some degree of precision.. This one has very little if any precision involved.. T

The stock S&W machine work was not much better (worse, really) than the Taurus. Reamers get dull/loaded up, lazy machinist's that don't care, worn out machinery, pick any two reasons. Jerry spent alot of time fixing the barrel which equals $$$.