My first project at GaugeMate was velocity testing, for which I used an Oehler 35P chronograph.
The results were vexing as I expected a velocity decrease but recorded a modest velocity increase.
My advice to the boss was to have independent testing done as it might be difficult for some to
accept our data. At that time the Sherman Bell/Tom Armbrust series was running in the Double
Gun Journal. That combo seemed a logical choice, so adapters and AA/STS ammo was dispatched. His
results, which we posted on the web, mirrored our results. Chamber pressure couldn't be measured
because the adapters constituted a chamber within a chamber. As the adapters were used by more clients,
some of them reported their testing results.

Two of those reports were very memorable -
The first was a fellow in the Upper Mid-West who was a 10-g 'buff.' He cast his own shot and alloyed the lead
he used. If that wasn't enough, he also counted pellets. We gave him as set of 10 to 20-g inserts for testing.
He reported velocity of the 20-g through a 10-g barrel to match 20-g through a 20-g barrel. He also opined
that patterning was improved - nice, but purely subjective. That is the segue to the second example.
A client with a 16-g Drilling wanted to have a lesser recoiling option. We sent him a set of 16 to 28-g adaptors.
Initially, he had a problem - they were too long for his chambers - that were allegedly 65mm. I told him that
some chambers were short and that he should have a gunsmith check it. Sure enough, his chambers were 63.5mm.
Chambers lengthened, he began his testing. He reported, among other things, that patterning was better than
16-g through his 16-g barrel. Nice, but how did he know. The answer was that he had a computer program that
allowed him to shoot at a large piece of white paper, photograph it and then have the image analyzed by the
program. He provided us with some excellent images and plenty of data. Obviously, he was not your average
shotgun shooter. What he was - was the retired president of a major American firearm manufacturer.

In either 2004 or 2005, I had some business that took me to the Federal plant in Minnesota. I was able to spend
time with the gentleman in-charge of shot shell production. He had never seen a chamber adapter before
and I explained the seeming velocity anomaly. He wasn't surprised. This is the 'Reader's Digest' version of his
explanation. Maximum pressure occurs 1" from the breech face. Adapters are 2 3/4" long, so the ejecta is
getting a full push for that length. Once the ejecta enters the bore, there is gas leakage but the trade-off is
less contact with the bore by the plastic wad. Anyone who has cleaned a shotgun barrel can see the plastic
residue. The wad acts like driving with your parking brake on.

Some thoughts on less traditional uses -
* If you have a 14-g gun, where do you purchase ammo? Fourteen to 28-g adapters were the answer.
* A well known shotgun writer had a 24-g Ferlib. We made him .410 adapters
* A group of 8-g Parker shooters had us make 12-g adapters so they could shoot skeet.

PS - Our adapters were designed to allow use of 2 3/4" cartridges in 2 1/2" chambers.