oldlou

I just got out my Conn 36A cornet and a BUNCH of old long and short shank cornet mouthpieces of various makes. With a Mitutoyo dial caliper I measured the shanks of all of the selected,( 26 of them ),mouthpieces at standard insertion depth, as shown by wear patterns. The majority of the short shank mouthpieces measure .380", while Bach shank pieces measure .390", again at the insertion wear mark. I then measured the I.D. of the receiver of my old Conn,American Standard, King, Holton, Martin, Wurlitzer, and several elderly Yorks. They all measured .375". My newer cornets made by Reynolds, York, Bach, King, L.A. made Olds, and Selmer all measured .383". This tells me that a Bach shank mouthpiece can be not only shortened, but a fine cut taken on the O.D. of the shank to reduce it to .380". Any competant machinist can do this within a matter of a few minutes.


OLDLOU>>

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Couturier trumpet
York Master Model trumpet
York Elite trumpet
York Airflow cornet
King super 20 Master Model cornet
King Liberty trumpet
Reynolds Professional cornet
Bohm & Meinl professional trumpet
Besson 10-10 trumpet with Holton M.F. bell
Olds Special cornet Los Angeles
B&H Sovereign cornet
G.R.Band Instr. cornet
Getzen Super Deluxe trumpet and cornet
Getzen Deluxe trumpet and cornet
Many others no room to list

Bruce H. Johanson

I use a Bach 3C without any problems in a 1947 Conn 12A...in the same horn I have used a Connstellation (gold plated) 5C-N.

dameyn

This thread is a little old, but interesting. I have a 1940 Conn 12A cornet, with 2 mouthpieces - the original Conn 4 Precision short shank, and a 1947 vintage Bach 1C with the Conn taper (0.060in/in). Back in those days, Bach did make mouthpieces to fit the popular Conn cornets. The Bach is 0.250in. longer, so projects 1.00inch into the receiver, whereas the Conn 4 projects only 0.75inch. But the shank end of the Bach is thinner, so the effective "gap" is less than it would otherwise be, and it plays well. BTW, the 12A has no step from the receiver to the leadpipe, so there is no physical gap. But the location and step at the end of the shank produces a similar effect to a physical gap.
Oldlou is right, a skilled tech with a lathe can reshape and cut down a modern mouthpiece shank to fit the 1936-1957 Conn cornets. Just remember, the unaltered taper of the receiver is 0.060in/in, instead of the modern 0.050in/in, so the taper as well as the length and diameter of the modern shank has to be changed to match that of the receiver. I don't think you could get it done for much under $100.
Be careful when buying Conn 4 mouthpieces - Improved Precision Conn 4 (post 1957) is not the same as Precision Conn 4 ('36-'57), and a trumpet Conn 4 won't work in the cornet. It has to be the 2.475 inch cornet Precision with lettering ("Conn 4") running the length of the shank. For the Conn 4, the ratio of total length to cup OD is 2.346, use that to estimate the length from the picture. Read the article "The Short and Long of Conn Cornet Mouthpieces" in the Conn Loyalist site.
Bruce - your 12A's receiver must have been reamed out somehow for your modern Bach mouthpiece to fit. Sticking a 0.050 taper shank into a 0.060 taper receiver would produce a wobbly fit. Or are you using some electrical tape on the shank to improve the fit?

Fidel

I was using a Bach 10 1/2cw and then a yamaha short shank on my 1946 80A cornet but neither was right. I now have an old Holton Galaxy mouthpiece with no indication of size or number.This mouthpiece is 2 1/2 inches long, fits perfectly and plays MUCH better than anything else I've tried. I guess I was lucky that the inner rim diameter is in the same general area that I like to play on.

ChopsGone

I've been hunting for the correct Conn mouthpieces for a pre-WWII 80A without much luck, but found a couple of possibilities. A Kelly (plastic) clone of a Wick 4B came close to fitting (taper's still not right, but it'll stay in there with a slight twist) but just didn't work well for me. The Curry VC mouthpieces seem to work a lot better, the 1HVC in particular. Thought I'd like the 1.5VC better, but it turns out that the big one is the better choice for me. The taper's still not the same as it should be for optimum fit, but again, a slight twist will keep it in place (and be very sure it's a very slight twist or you'll be breaking out the mouthpiece puller). Those mouthpieces produce just the sort of vintage cornet sound I wanted.

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Vintage Olds and Reynolds, yes sir, yes sir, one gazoo full.

Calicchios, Besson, Kanstul Bessons, Selmers, etc.

F.E. forgive me, even a Bach Strad (but I like the others much better)

bockhaus

I may have just found a source for a Conn short shank mouthpiece for my newly acquired 1948 12A. I have an appointment next week to check it out, but it sounds like this guy has a large quantity of various vintage mouthpieces. Maybe I'll luck into some other good finds.