BSA SuperTen MKIII "Carbine" in .22

[Crank]

I put this BSA up a while back on the classifieds on one of the other forums since it was languishing unused in the gun safe. I warned people that if it didn't sell, I was going to do something drastic,,,,it didn't sell.

So here I now present to you the BSA SuperTen MKIII "Carbine" in .22cal. with a 250mm barrel and shroud shortened accordingly. I also re-purposed a baffle unit that I had made for testing on another air rifle and does a much better job in this one. It's pressed in place so I unfortunately did not photograph it before I installed it in the shroud tube.

The velocity actually crept up to around 830fps, but I was very pleased that I hadn't lost too much velocity. IIRC, I was around 870fps before the surgery (it's been quite a while since I last chonographed it) Since the picture, I refaced the end of the shroud and hit it with some matte black paint, so it looks better now. Now I will look forward to a session at the range and see how she shoots.

Enjoy!

Mark

[Hobbyman2007]

Nice job on the shorty. Have you installed any kind of hammer debounce devise ? I would imagine with that short of a barrel it would not be the most efficient , at least you took care of the noisy part.

[Nomadic Pirate]

I really, really like that !!

[Crank]

Hobbyman,
I haven't done anything with it. I bought it used several years ago, took it to the range, it shot okay, then it sat in the safe until now. I was going to sell it since my current affinity is towards bullpups and my only "long" PCP is a Theoben Rapid in .25. Since it didn't sell, this is what happens .With the velocity sitting around 830fps out of a 250mm barrel, I'm not seeing efficiency appearing to suffer to bad. Once I get to the range and see what I can manage for shots on a fill, then I'll worry about it. I'm not familiar with a de-bounce issue on these, so I would appreciate your input.
Thanks

NP,
Total invested time was less than 2 hours from tear-down to test fire, so I'm happy with it and it swings much easier. The factory shroud is a very heavy wall tube and I probably knocked close to a pound off of the weight.

Mark

[KnifeMaker]

Man, I Love it!


If you have more baffles for it, loose at least two of the springs. They do nothing but assure the baffles don't come to the exact place on each shot, and use up valuable space for more sound deadening baffles.


How Many mm did you remove from the barrel,and what was the difference in velocity?


This AG now "Looks Right"!


Knife

[Crank]

Knife,
Again, thanks for the compliments. I did not reuse any of the factory baffles, I had an airstripper/baffle assembly that I had milled out for another application. The barrel is about 9" shorter and the shroud about 10".
Like I said, it has been years since I put a pellet through it and just as long since a chronograph session, so my best guess is about a 40fps loss.

This is the only .22 PCP I have, so it doesn't have any competition. The accuracy never seemed particularly stellar and looking at the crown it was rather roughly done from the factory. I've spent over 30 years gunsmithing and all of those silly accurate PB rifles out there don't have choked barrels, so I wasn't too concerned about eliminating it from this one.

Mark

[LDP]

Pellets and bullets are two different animals. some pellet rifles shoot just as good unchoked and some dont. From what I have read is that the hammer forged BSA barrels dont have a single point in the barrel that is choked. Instead the bore slowly tapers down from the breech to the muzzle. The most famous BSA smith and designer of some of the parts John Bowkett says to never cut a bsa barrel off at the muzzle end but instead shorten it from the breech end. He knows what hes talking about but I also know things dont always go the way you think they will. It will be interesting to see how this barrel reacts to being cut from the muzzle end.

[RVaughn]

That is awesome! !  I love a bottled carbine..

And wish that someone would make a bottle fed bullpup that was around the $500 mark and didnt weigh 10 lbs unscoped!

[MP44]

It is hard to sell the older generation pcps, they aren't collector's items, just older technology and with the prices of new and used new tech Daystate XLs and Streamlines it's hard to move them unless the price is so low they would be hard to pass up.

Nice job on the modifications, I wish I had the equipment and skill to do things like that.

[Tweeter]

That gun looks awesome Mark, nice job.  I have always wanted one of these Supertens and saw your listing but I'm left handed.  Let us know how she shoots.

[Crank]

Well, got to the range yesterday and other than reminding myself why I have a quick fill adapter ordered, it's a winner! Got the scope on target quickly, just as the wind was picking up, but even with wind it was keeping the groups around 1/2" at 50yds. I was very happy with it's performance and I'm certain that accuracy improved considerably. That was part of the reason I hadn't shot it much, the accuracy wasn't horrible, just not something I could count on for a "minute of squirrel" at 50yds. My buddy was watching my groups and he kept saying "dead squirrel". The only annoyance was the bolt handle kept coming loose and the knob is pretty small, so I think a custom oversize knob and a bit of Loctite should address that problem. Time to fire up the lathe!

Mark

[Nomadic Pirate]

Gotta love it when everything comes together,
....again, that gun just looks super sweet.

[rkr]

Well done, those short BSAs are really nice guns. It's too bad that Ultra is more expensive in US than a Scorpion, you can get one for around 400£ in UK and they are extremely popular there.

[Crank]

Thanks to both of you for the compliments. It just worked out well that I was able to re-purpose an otherwise functional, but dated model, into something fun and cool looking.

I ordered the quick-fill conversion from Dr. Bob's in the UK and it should be here in another day or two. Pulling the bottle to refill and struggling to screw it on far enough to open the valve was tedious. Now I will be able to air it up like my Theoben and I gain a pressure gauge at the same time. We corresponded back and forth to determine if it would push the bottle too far forward, but he is confident that the original valve was long enough there shouldn't be an issue. I was lucky that he had just gotten another batch of Theoben magazines and had some .25's that weren't listed on his site yet, so I have two more coming along with a replacement plate for another magazine that was missing when I bought the rifle years ago.

rkr,
You have quite the collection of BSA's and I had no clue what the Huub Viking was. I am assuming that is what you have pictured in your avatar.

Mark

[rkr]

rkr,
You have quite the collection of BSA's and I had no clue what the Huub Viking was. I am assuming that is what you have pictured in your avatar.

Mark

Somehow those BSAs add up over time, I actually have one at works that's made from spares I had lying around Huub (the guy who makes HUMA regulators and shrouds) made a short serie of BSA Ultra based bullpups called Viking few years ago before he went big on aftermarket parts, they were rather short measuring at 50-60cm. I managed to get one of them, a great tool for backyard pest control:

200mm-shroud-2_zpse94340df by abbababbaccc, on Flickr

[LDP]

You mentioned a possible bad crown I would have liked to see accuracy tests done with a crown job then after the barrel was cut down. It would have been interesting to know if it was a bad crown and then compare the accuracy between the original length with a good crown and the shorter length. It sounds like its shooting good. We will never know if that particular barrel improved stayed the same or lost accuracy if in fact it had a damaged crown to start with.

I thought about cutting down an S10 I have since its tuned for 12 fpe and has an 18” barrel. I never did cut it because its very accurate. I didnt want to cut from the muzzle end and possibly lose accuracy.

[Crank]

rkr,
That's a neat little rig, looks similar to the early version of the Lelya, but with the benfit of magazine feeding. Having one of the current Lelyas I think I would like to get an early one also, just because they were so streamlined. My current one is nice, but it's a bit more full figured.

LDP,
You are spot on, a re-crown would likely have made a world of difference keeping it stock length, but when my lathe called out for a sacrifice, here's what happens. It's a safe bet that if there was any potential accuracy loss, it was not enough that I would lose sleep over. Without a doubt, I paid a penalty for velocity, but the handling qualities the rifle has now give it a new lease on life.

Mark

[LDP]

So I am going to resurrect this thread and yes its for a good reason Crank have you shot the shortened S10 anymore since the last accuracy report you posted after the cut down in this thread?

I finally decided to cut my S10 down from 18" to 10". I took it all apart and figured I would push a pellet thru the bore and check for how tight the choke was and see how far from the muzzle the choke extended. I pushed a JSB 10 gr. pellet thru and it has light contact with the bore the whole length. There were no tight spots and no choke just very light contact the whole distance. I tried an AA 8 gr. pellet and got the same results. So once I found out my bore has no choke it was a go for cutting it down.

I already rebuilt the reg after receiving the S10 turning it from an fac reg to a sub 12 reg. So I should be all set for the shorter barrel except maybe some fine tuning of the hammer spring. I am going to add a full shroud on mine making it look just like the S10 carbine bull barrel model. I hope my accuracy stays the same but we will see. I will make a new thread after the work is done detailing what I have done to my S10 since getting it in a trade a couple years ago.

[Nomadic Pirate]

So I am going to resurrect this thread and yes its for a good reason Crank have you shot the shortened S10 anymore since the last accuracy report you posted after the cut down in this thread?

I finally decided to cut my S10 down from 18" to 10". I took it all apart and figured I would push a pellet thru the bore and check for how tight the choke was and see how far from the muzzle the choke extended. I pushed a JSB 10 gr. pellet thru and it has light contact with the bore the whole length. There were no tight spots and no choke just very light contact the whole distance. I tried an AA 8 gr. pellet and got the same results. So once I found out my bore has no choke it was a go for cutting it down.

I already rebuilt the reg after receiving the S10 turning it from an fac reg to a sub 12 reg. So I should be all set for the shorter barrel except maybe some fine tuning of the hammer spring. I am going to add a full shroud on mine making it look just like the S10 carbine bull barrel model. I hope my accuracy stays the same but we will see. I will make a new thread after the work is done detailing what I have done to my S10 since getting it in a trade a couple years ago.

Can't wait to see pictures of you short BSA,...love mini-carbines

[rkr]

9-10" is about the shortest you want to go in .177, I have 8" .177 barrel and it needs about 150 bar reg pressure to reach 12 fpe. Those short barrels can be extremely accurate though, I got 0,05" ctc groups at 20 yards with mine. Did you cut the barrel from the breech end?