More from Kuduae, from a reply to a previous thread of mine:

Re: Aussie Copper for M1910 [Re: Rothhammer1]
#309552 - 12/28/17 02:47 AM

Quote:

Does the Speer 235 need to be set out to maximum overall length as you had with the Barnes TS X? The loads I sent back to their maker with the low, narrow (8X57) shoulders had bullets of that or similar profile and they did not feed. The first round loaded would get 'jacked' as a third went in. Two in, then stuck.

(Kuduae:)
In the pre-1924 Mannlicher – Schoenauer models M1903, 05, 08 and 1910 magazines the cartridges are held to the cartridge carrier rotor by flanges machined in both receiver and magazine bottom. The rear one, about 5.5 mm = .22" wide guides the cartridge bases and is no problem. The front one, about 8 mm = .32" wide, holds the bullet noses.M 1924 and later models introduced a seperate guide ring instead of the machined bullet guides. My old photo shows M1910 magazine parts on the left with the bullet guide at the front end. On the right are the simplified parts of a post-WW2 6.5x68 "Magnum" magazine without such bullet guide, but with the neck guide ring.

Cartridges for all these old M03 -10 rifles must be loaded close to maximum oal, so the bullet noses may be held to the carrier spindle by the guide flange. If, f.i. you try to convert a M03 6.5x54 into a flat shooting varmint number by loading light, short, pointed bullets that are too short to be engaged by the guide flange, the front ends of the cartridges in the magazine will drop away from the carrier spindle and jam. This is your "third round problem"! To avoid such jamming all cartridges for the old M-S models have to be seated close to maximum magazine oal, disregarding any existing crimp grooves. In the 9x56 M05 the 200 gr .35 round noses, designed for the .35 Remington, are too short if seated to the crimping groove. This applies especially to bullets with slimmer noses than the old blunt round nose, like the TTX or the Speer 235 gr. Loaded cartridges for the M1910 should at least have a Diameter of about 7.5 =.30" at 70 mm = 2.75" from the base for proper function in the magazine. Other bullets with very slim, pointed noses will be hopeless, as they may be too slim 8 mm behind the point to be held properly to the spindle.