Anyone ever done any tuning on the BSF/Bavaria 55?

[evert]

I have two Bavaria 55's, one deluxe, and one plain.
As the title says, has anyone done any tuning on these rifles?

[Duggan]

Venom did.

[evert]

Any hints on the modifications they performed?

[Duggan]

I have started a thread on it and listed what they did, its next to this thread....

[kevin.ronnie]

Some yrs ago I spoke to the chaps at Venom and they told me they did very little with internals of the venom Bavaria but did try to improve the trigger , I personally have found that bringing the power down to 10-10.5 Ftlb make a 55, 60 or 70 much nicer rifles to shoot with negligible power loss, hope this is of some help.
Rgds Kev

[evert]

I have started a thread on it and listed what they did, its next to this thread....

Thanks!
I didnt read that thread as carefulley as I should, silly me!
Got a bit frustrated because photobucket are blurring the pictures.

I see that they did transfer port work, do you know if they did any other internal modifications?
Are the dimensions of the spring known?

[Hsing-ee]

The BSF B55 is a very small light rifle with a very strong spring and lots of pre-load. This makes it very jumpy on firing, which can make it difficult to master it and deliver good accuracy.

When I had one I fitted a standard spring from Maccari in the USA and this, without spacing, gave about 8 fpe in .177. With spacing it will do 12 fpe but the recoil is much harder. I found it nice to shoot at about 10 fpe.

The trigger is not fully active, so as the mainspring pressure increases, so does the effort needed to pull the trigger. So a spring operating under less stress, to produce 10 fpe, makes the trigger nicer to use, again increasing accuracy.

Also, if I was 'tuning' one of these older rifles I would get a adaptor and a parachute seal and replace the leather piston washer. One would have to measure the transfer port volume and swept cylinder volume and perhaps sleeve the transfer port to get the right compression ratio. Buttoning the piston might also make it a smoother shooter, as well as the obvious top hat and spring guide. Replacing the leather breech seal with a couple of 'O' rings may help seal it more efficiently.

[evert]

A synthetic seal will probably be my first move if I find the time to do any work on the 55.

[Duggan]

A synthetic seal will probably be my first move if I find the time to do any work on the 55.

I had a conversation with Steve from Vmach he actually worked on the Venom Bavaria back in the day. The leather seal was actually kept in the end because a synthetic one didnt improve things. But hey that was over 30 years ago.

[PhatMan]

evert,

In the late '70s I had a 0.177" Wischo 55S (which IIRC, was a BSF 60 or 55 ?).

I stripped it and gave the internals a good clean, de-burr, polish and lube.

The only chrono that I had access to was home-made, and gave ca. 10 ft.lb as the output with RWS Meisterkugeln, though how accurate that was I do not know !

The only intensive work I did to the Wischo's innards was on the trigger - a good smooth, polish & burnish with graphite powder, and it did improve the pull a lot, though it was still around four (4) lb.

Have fun & a good weekend

Best regards

Russ

[evert]

Thanks to both of you. Interesting to hear about Popes' experiences! Probably wont keep me from trying, but a seal change is reversible.

[I. J.]

A synthetic seal will probably be my first move if I find the time to do any work on the 55.

I also replace the (usually flat) leather breech seal with one and a half 'O' rings. The half because it has a sloping breech seal recess.

HTH
Ian

[Hsing-ee]

Ive said it but as Im not afraid of being boring, the BSF is the most typical of air-rifles i.e. if I had to chose one rifle to represent all the Nation of springers I would choose a BSF break barrel. It's well made but not posh, conventional in design and sits right in the middle of the development of the springer between the 1907 Lincoln Jefferies BSA and the TX200 of today.

[DM80]

I've owned a couple of Bsf airguns a 55 and 70 and serviced and tuned quite a few always found they shot nicely at around 10.5 ftb with the standard leather washer and spring fitted with delrin guides and the right lubes etc fitted a synthetic piston head to a 55 I found it wasnt as good as the leather head its locktime was faster but harsher slight power increase but I eventually put the leather head back shot much sweeter,
But to be fair the Bsf was a strong well made gun but not a great gun not in the same class as HW Fwb or originals of the period.

Dave.

[evert]

I've owned a couple of Bsf airguns a 55 and 70 and serviced and tuned quite a few always found they shot nicely at around 10.5 ftb with the standard leather washer and spring fitted with delrin guides and the right lubes etc fitted a synthetic piston head to a 55 I found it wasnt as good as the leather head its locktime was faster but harsher slight power increase but I eventually put the leather head back shot much sweeter,
But to be fair the Bsf was a strong well made gun but not a great gun not in the same class as HW Fwb or originals of the period.

Dave.

More experience against seal conversion.. Seems like a syntetic seal might not be worth the trouble then.

Do you have any spring recommandations?