doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Lengthening 2 1/2 chamber on Nitro Special

Is it possible to lengthen a 20 ga nitro special from 2.5 to 2.75? Is there enough meat there? What's the average cost to have them both lengthened? Thank you?

Certainly no expert. But I am surprised a Nitro Special has short chambers

But possible yes. Enough meat. I would think It would have to be measured to know - it is an old gun someone could have worked on it before

Me too. Are you sure they are actually 2.5"? I woild expect them to be 2-3/4" or at least 2-5/8".
Anyway, if it is short. Lengthen away.

A 20 gauge chamber gauge is .685, get or make something of that diameter and stick it in the chamber and see how far it goes in.

Mike

http://www.ebay.com/itm/VERMONT-685-MINUS-PIN-GAGE-AB1562-1-/361425937368?hash=item5426aa23d8:g:FsEAAOSw~bFWPNIi

The Flues model in 20 ga. was chambered 2-1/2" until the end of production in 1926. The NID was introduced in 1926 and the 20 ga. had 2-3/4" chambers from the start. With the Nitro Special being introduced in 1921 it is possible that the 20 ga. guns may have been 2-1/2" for several years.

Ok thanks for the help! Saw one advertised with 2.5 chambers.mmay be a typo.

Beginning with the first NID catalogue in 1926 they state -- "Unless otherwise ordered Ithaca .410 Cal. and 20 Gauge guns are chambered for the standard 2 1/2 inch shell, 16 Gauge for 2 9/16 inch, 12 Gauge for 2 3/4 inch and 10 Gauge for the standard 2 7/8 inch shell." The 28 gauge doesn't appear in NID period catalogues until 1932 though they did make some. Beginning with the 1927 catalogue the sentence is changed to -- "Unless otherwise ordered Ithaca .410 Cal. guns are chambered for the standard 2 1/2 inch shell, 16 Gauge for 2 9/16 inch, 20 and 12 Gauge for 2 3/4 inch and 10 Gauge for the standard 2 7/8 inch shell."

Unfortunately, the early Ithaca-built Lefever Nitro Special flyers don't mention chamber lengths --

I suspect the earliest 20ga NS's had 2½" chambers, though not positive. It would be interesting to know if when they were changed to 2 3/4" if any mods were made other than length of chamber, somehow I doubt it.

The 3X5 card technique works very well
http://www.lcsmith.org/faq/chamlgth.html

Let us know

Not sure about chamber length or barrel thickness in chamber area, but I used 3/4oz light loads in WWI vintage 25" 20ga Model 12 that had short chambers. I use same stuff in my 4.5lb pump. You can get short shells from RST or use light loads from Fiocchi, but those from Italian company are 70mm not 65mm length. Anyhow light 70mm shells aren't likely to hurt that Le Sodbuster Speciale if it is in very good mechanical order.