Holton 51 (1960) MP/gap advice ?

[zr1100]

I have a Holton 51LB that has a 1.24" receiver depth (rec. opening to venturi ledge).
Most of my modern MP's insert less than 1.04, so it's always a .20+ gap ahead of the venturi (5mm+).
Does this sound normal/OK for a horn of that period--ie. I don't know if MP's from the 1950's-60's era fit the horn any differently from way the current Bach/Yamaha/Schilke/etc. MP's do ?
Thanks
(of course I'm mainly interested if a smaller "gap" might improve playability/mild stuffy feeling. Am getting some custom shims that match receiver ID and venturi size, and wondering about where to start if experimenting with gap)

[cgaiii]

Don't know much about the Holton, but in terms of gap, your Bach and Schilke mouthpieces will insert to different depths as a rule. Schilke mouthpieces generally insert deeper and will lessen the gap.

When I was experimenting with gap on my horns, I bought a set of shims to match the horn from Jason Harrelson.
https://www.whyharrelson.com/store/p267/Mouthpiece_Gap_Shims.html

They allow you to play with the gap. I did not find them to be a permanent solution since they come out if you swab your leadpipe, etc. However, they do allow you to play with the gap without any alterations to mouthpiece or horn. Now, they do adjust the gap upward from the venturi, which might change things a little.
After using the shims to determine that there was a good effect for some horns.
I got a Gap Modulator from Jim New (credit to Lou Finch for telling me about this). This requires modification of a mouthpiece, but then you can dial in the gap quite precisely. Currently I have one mouthpiece modified this way and use it on multiple horns, but just today was thinking I would like to get a couple more done and be able to just set them for a particular horn.
http://james-r-new.com/accessories/gap-modulator-50.html

You could go an extra step and get sleeves to match what you found with the gap modulator, but I have not taken that step. Lou did as I recall.
_________________
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