Breach seal performance improvement

[Benelli B76]

I normally change breach seals at the same time as doing major spring and piston seal maintenance, but have started to do chrono tests before and after just a breach seal replacement. Have been surprised at the difference it can make, even if the old seal does not look completely finished. Did one yesterday that jumped from 454 fps 7.32 ft lb to 565 11.34 ft lb. This seems abnormally high change, has anyone had similar result ? Started to keep a log.

Baz

[averageplinker]

Hi,
I recall Mr Pope noting the use of an HW seal in BSA rifles could be worth 1 ftlb.

I have an HW85 & HW97 which I intend to replace the seals on, I will do before and after readings when I get a chance.
Cheers
Rich

[junglie]

Yes. I have a bsf S70 that went from 8 ft/lbs with a new standard spring to 10.5 with the old leather seal replaced with an o-ring stuck in with a glue gun using soft sticks. On the other hand i tried the hw seal in my challenger & it went down 1 ft/lb ,as unless you trim the back of the hw seals EXACTLY to fit the bsa recess they stick out too much & get chopped by the breech closing.

[Mr. Gen]

customairseals are a marked improvement in Weihrauch over the original breach seals, and their piston seals are always good as well..

[Benelli B76]

customairseals are a marked improvement in Weihrauch over the original breach seals, and their piston seals are always good as well..

My seals are all custom, piston and breach, would never buy them.

Baz