Still Searching..Ross Mark III Barrell Threads specs...?????

Dear Ross-ophiles,
I am still searching for details of the Barrel Thread for the M1910 Mark III Rifle.

I know it is a normal form ( Withworth, 55 degrees) but don't know what the Pitch is ( Threads per Inch) or the Thread twist, Left Hand? ( like the earlier Mark I and II) or Right Hand? ( like most "normal" rifles)

Any help would be appreciated.....I have half a dozen Indian Army DP Ross rifles ( hole cross drilled through chamber) and would like to Pull the Barrels to rebuild them ( sleeved chamber, etc.).

Thanks, Merry Christmas / Joyeux Noel to all.
Doc AV
Down Under.

Best idea is to let the dead rest! Sleeving the chamber? Madness.

DocAV, a familiar voice from other forums, excellent. Several years ago I tried to find definative information on this little bit of firearms minutia. I read the Ross Rifle Story complete (which you likely have) and only found a reference to 16tpi on page 42. The index in this tome only waves in the general direction of information so I may have missed something. A member in this forum stated some time ago that the MkIII had a buttress thread of 16 tpi but I don't know the original source. Perhaps he will respond more completely. On page 46 of TRRS it says "Ross had switched to the U.S. Standard thread for his barrel", so maybe it's not Whitworth. All very general information to very specifically needed information, sorry. When you get around to actually removing a barrel I and others I'm sure, would love some definite specifications. I don't know if it is efficacious to sleeve a chamber but I believe it has been done successfully in the past, the Italian Vetterli-Vitali had the entire barrel and chamber sleeved. In any case the process and end result would be very welcome. Regards. Tom

Even if the barrel is in perfectly good shape, the rifle very well may have been DP'd for other dramas. Why risk it?

Sorry Doc, only have the 1905 with the square threadform and left hand thread, it has a setscrew to lock it up, maybe worth checking the later one, it gets a bit frustrating when you have to wind something hard all the way only to find galled threads due to setscrews.

I have some Mk. III barrels in the shop. Will get measurements when I go there.
As far as sleeving a drilled chamber goes, I'm rather uneasy.

Had a look at a Mk. III barrel this afternoon. Major diameter of threads is 1.120, shank length is .732. Threads look to be 12 t.p.i., square. These measurements were made with a digital caliper, not a mic., but will be close.

Thanks for the Thread details, BUT one question remians...Left Hand or Right Hand????

There is a Locking up Pin underneath, so that is not a problem...but which way to turn it is...

As to "sleeving chambers" I do it regularly with MG barrels which have been DP'd by cross drilling, Pinning,welding etc. These sleeved-chambered barrels are then Proof-tested using a 30% OP Ball load ( several) before conversion to Blank Fire. US MG dealers of a certain Note, also sleeve DEACT (US DEWAT) Barrels for reactivation to Ball, fulltime.

The Ross Barrel is actually Much meatier than a lot of MG barrels (Bren, BMG, etc) so a substantial Sleeve can be applied. Of course, it is not a job for an old lathe or drill press...it requires 10,000 's accuracy in diameters, and even "Hot fitting" ( heat barrel, chill sleeve) for an interference fit, with both parts "tinned" with silver solder, for subsequent adherence.

As to why the Indian Ross Rifles were DP'd, they were NEW ( 1916) Ross Rifles sent to India after WW I and during the 1930s; they were almost immediately converted to Drill Rifles, by
(a) Drilling a 5/16th Diameter hole across (horizontally) the Chamber section, (b) Cutting the Woodwork with a 1/2" to 5/8" wood bit to allow clear view of the Chamber Hole ( cutting into both the Lower Forewood and the Upper Hand guard, Both sides). (c) the Firing Pin was Nipped off, and (d) sometimes the Bolt face was soldered over the FP hole.
(e) A new 5066-xxxx Serial Number was applied ( metalwork and woodwork) as well as the letters "DP" to various metal Parts.

All the Indian DP rifles I have are all "LC" chambered rifles ( 1916 modification), are all virtually brand new internally ( no signs of Wear etc, except for Bolt and Boltways), and have signs of external Drill wear and tear ( wood nicks etc, Buttplates showing gravel marks.) Bores are "factory new" ( probably never fired).

I consider these particular rifles excellent choices for "Re-building" to functioning Ball firing rifles..even if that may only be for Proofing of the Repairs...nearly all my inventory of rifles etc are used as Blank-firers in Movies, but for Insurance Purposes, they have to be "Ball Proven".

One must remember, whilst a lot of "out of spec" (unrepairable) rifles become "Ds", NOT all DP's are "Out of Spec"...they used a heck of a lot of Serviceable ( even NEW) Rifles...India did the same with P-14 Enfields as well ( some Weedon Standard, some ex-WW I ( volley sights etc)...got some of these as well ( with the Ross Rifles).

Regards,
Doc AV

Right hand threads.

barrel threads