Springer BR

[32:1]

Thinking of a BR25 springer project and can get an 80 cheap to cut about

Id think 7-8ftlb plenty and the 80 is a nice heavy platform, anyone gone down this route as Id like to know if ultra short strokes or smaller bores are the way to go

Chris

[tinbum]

Thinking of a BR25 springer project and can get an 80 cheap to cut about

Id think 7-8ftlb plenty and the 80 is a nice heavy platform, anyone gone down this route as Id like to know if ultra short strokes or smaller bores are the way to go

Chris

It should be good, but I think a full length 77 might be easier to alter for that power with similar weight.

If going the 80 route, reduced bore is ultimately better, maybe an HW30 piston?

[32:1]

The 80 is price focussed as its very, very cheap

Or I dive into one if these Cometas as pistons are lightweights

How light can an 80 piston be before it gets messy ?

Id think a stroke of 60mm is more than enough, longer latch rod route I guess

[Hsing-ee]

Isn't long stroke narrow bore soft spring the ideal nowadays? Getting an HW30 and sleeving the cylinder & barrel with nice thick steel tube might be the cheapest way through this ...

[simona]

A sidelever would be far easier to cock and load from a bench. My life's already chock-full of boredom and frustration but, if I was going to try benchrest with a twanger, I'd probably go for a reduced cylinder Original 48/52.

[Shed tuner]

reduced bore is the way to go for BR... much less recoil/bounce. A 24mm conversion will make full power at 80mm stroke if you want to do that at some time, but with a 60-70mm stroke should be almost recoilless

I'd have thought for 25 yards, 7-8 FP would be plenty, unless it's blowy ?

[Shed tuner]

if I was going to try benchrest with a twanger, I'd probably go for a reduced cylinder Original 48/52.

Agree with this...

[32:1]

After a bit of searching the smaller bore route seems better so the 80 is out of the window and Ill focus on the Cometa as pistons are very lightweight and a loss in stroke should deliver a smooth action

Ive a 400 now running a 20mm nose and it still needs a trim to stay legal and its very nice to shoot, so a 40mm nose and an even lighter piston may work at 7.5

[TonyL]

Hw77/97.

[32:1]

Hw77/97.

I was going to use the 80 as price is low enough to molest it and not worry about it, but have decided to use one of the 400’s I have here, plus parts are cheap to put it right if it wrecks

[TonyL]

I was going to use the 80 as price is low enough to molest it and not worry about it, but have decided to use one of the 400’s I have here, plus parts are cheap to put it right if it wrecks

Understood. Good luck with the project. I hope you achieve the results you desire. Keep us updated.

[Shed tuner]

I was going to use the 80 as price is low enough to molest it and not worry about it, but have decided to use one of the 400’s I have here, plus parts are cheap to put it right if it wrecks

sleave down the 80 to 24mm... it's not really a tough conversion.

[32:1]

sleave down the 80 to 24mm... it's not really a tough conversion.

Trouble is my 400’s shoot better than the 80 as is, plus Ive got to buy the 80 so there’s a few quid that can go towards some spare 400 parts, pistons are only £22 so Ive ordered a couple and plan to shorten stroke by 40mm to start with, Shauny has made guides for the 400 now and Ive modified the trigger so Im on my way

I plan to cut a piston in half and weld in a section so I keep spring room in one and the other Ill try a nose extension and a shorter spring to compare

I can afford to fail this way as Ill just put original bits back in 👍🏼

[Shed tuner]

fair enough... I thought you already had the cheap 80...

Nose extension will not be a smooth as the longer rod version, as the initial acceleration is a bit higher, and/or the final preload will be lower, due to the shorter spring... but it might be every bit as accurate, so always worth trying.

[32:1]

fair enough... I thought you already had the cheap 80...

Nose extension will not be a smooth as the longer rod version, as the initial acceleration is a bit higher, and/or the final preload will be lower, due to the shorter spring... but it might be every bit as accurate, so always worth trying.

Ive been looking and the longer piston latch route it seems to be the way to go agreed, but the pistons are cheap so I thought stick a nose on it and chop the spring?

Ive tinkered with one of these 400’s and found a 20mm nose works perfectly as it puts a little preload on a virtually zero preload setup and still remains just legal. Im now thinking a 7.5ftlb setup just might be fantastic, I suppose its the fun of boinger tinkering