Sunday, 11 June 2017

The Original Japanese Mk II 177. Sharp Innova Multi-pump Air Rifle, Review and Accuracy Test


The Sharp Innova is not a pellet fussy air rifle.

Oh no! Not another bloody blog about the bloody Innova!


In my most honest and humble opinion the Sharp Innova is an awesomely but simply designed multi pump air rifle, people in general tend to either love it or hate it, i myself, you may have gathered, i love it (Not unlike Jeremy Corbyn, old, honest, and reliable). This is the original Japanese Sharp Innova i'm talking about,not the later Chinese and Pacific Rim copies, and not that bloody awful Webley Rebel either.

A well thought out design, nice and simple.

Externally it has a rather blocky stock and forearm (the wood is solid and does not splinter or chip as a rule),

Though stained and varnished, the woodwork is solid.

a polymer/plastic reciever,

Even the plastic reciever is pretty tough.

and front sight housing that supports the metal barrel, pump tube and pump arm, a 10mm rifled inner barrel, and annoyly brittle plastic outer barrel sleeve

Some parts can be easily bodged

 At 90 cm's long the rifle feels compact and well balanced,

Compact little powerhouse.

The stock is held onto the reciever with one screw that secures it to the brass valve within the compression tube inside the plastic reciever, this is the heaviest and most solid part of the rifle body.

Without this one screw the whole thing falls apart.

The forearm is held onto the pump arm with two metal pins, this gives a comfortable hold for pumping.

A small piece of rubber inside the pump arm reduces the noise of pumping.

  Besides having MkII written on the reciever the only other things to denote it externally as a MkII are the plastic buttpad,

It may be ineffective as a butt pad but it does add character.

and a metal safety switch on the metal trigger guard that stops the plastic trigger from moving when engaged. There is also a small ajustment screw on the trigger which alters 1st stage travel, these tend to be missing on most 2nd hand Innova's and really is of no great loss too the airgunning world.

The safety is not automatically set, which to most people is a bonus.

When Sharp Introduced the Innova to the public in the late 70's/ early 80's the idea of all this plastic went against the grain with a lot of people, but the majority who actually got to use one soon realised it was a very accurate, powerful, and reliable air gun. The use of plastic for many external pasts proved to make it very robust with no blueing to scratch up, after 30 odd years though the plastic has started to get brittle in places and i've had my fair share of Innova's with chipped and snapped off bits. Still i have managed to fix, bodge or by-pass many of these problems, ending up with a rifle that handles as good as it ever has.


Loading pellets can be a little fiddly at first, until one gets the hang of it. With the rifle held at a 45 degree cant and a pellet placed at the bottom of the loading port, the pellet will easily roll into the breech with a small tilt of the rifle. 

The problems of a small and fiddly loading port can be easily overcome.

The bolt is sprung loaded, when the small catch at the rear of the reciever is pushed down the bolt springs open. 

The recess in the bolt is for the lever to hold it in place.

Once the pellet is loaded the bolt is pushed back in place into the reciever and seals the breech, the catch lever is pushed back up under spring tension to hold the bolt in place. 

Bolt held in place under spring tension.

Two O rings on the bolt seal the breech, loading the pellet is best done after the rifle has been charged/pumped up.

The rifle is kept under 12 ft/lb using an adjustable blow off valve built into the pump head, most Innova's will blow off excess air and leave enough air pressure to fire a pellet within an 10 FPS spread over many shots.


The large pump head houses the valve for blowing off excess air pressure.

Before any tinkering is done on the rifle, 7 or 8 pumps will charge it enough for one full powered shot.  After fine adjustment of the pump assembly, it is possible to get 12 ft/lb with 4 or 5 pumps in .177 and 3 or 4 pumps in .22.

 Supporting the rifle by the back of the reciever and pistol grip allows for the most effective pump stroke.

Squeezing the trigger will dump all the air in the valve and fire the pellet, this rifle has an exhaust valve where a sear block holds the firing pin in place. Moving the sear out of the way of the firing pin allows the pressurized air in the valve to force the pin back, with the valve empty a spring will push the firing pin back in place to seal the valve for the preparation of the next shot.


An adjustable butt pad would be a good investment for this rifle.

The pump arm swings back 60 degrees to allow air into the compression tube,


The pump arm at full extention, the front sight housing stops the pump arm from going any further.

more force is needed on the pump arm the more pumps applied. The same with the trigger pull, because the more pressure that is in the valve the harder the firing pin pushes against the sear block and the harder it is to move it with the trigger. At 12 ft/lb the trigger release is still comfortable so the Innova is still very accurate, this is due to the trigger pull, a decent barrel, and the near zero recoil of a pnuematic rifle.


Shooting offhand in windy conditions does not make for the most accurate of groupings.

Fired from a rest in good conditions sub half inch groups at 25 yards are easily achievable, however a scope is usually needed for these better results.

I must get a pellet trap as the kids get really annoyed when i shoot their toys.

A simple rear open sight that clamps onto the scope rail comes fitted to the rifle, unfortunatly these tend to get lost easily as is the case with all but one of the many Innova's i have had the good fortune to own or work  on.

An Innova in decent condition for sale at around £200 will sell easily, and if it's well cared for all it's life will still be working and have all it's original parts. However, if someone has tried to ramp up the power on one in the past, it will have put excessive wear on a lot of the parts. Luckily replacement parts are reletively cheap and available from various places, they are also pretty easy to work on (I've done more than enough blogs about Innova's in the past to prove this).

My opinion? Good air rifles, i love 'em.


All the best,

Wing commander Sir Nigel Tetlington-Smythe



















Friday, 28 April 2017

.177 BSA Cadet, A Review and Other Bits and Bobs


For an old air rifle that i always thought a bit of a smallish youth rifle, i was pleasently surprised to find it both considerably larger and heftier when i first laid my hands on one. 

109 cm from tip too tail

The very first thing i did though was to put her over the chronoghraph to get 4.56 ft/lbs with JSB Exacts, she was old, complete and in fairly good nick and i reckoned things could only improve from here on in.

This has the look of a sporting rifle in the 50's

 BSA was responsible for the production of over 50% of all British small arms produced during WWII, so roll on 1945 and they decide to go back to an increase in thier Air rifle production and the introduction of thier new Cadet air rifle. Capable of putting out 8 ft/lb and advertised as being able to take rabbits out to 50 yards this rifle was popular amongst young adults and adults alike, trade description was not an issue in those days. Maybe if you could throw the thing 50 yards you could possibly concuss a rabbit, with a full wooden stock and heavily engineered steel construction the rifle had some interesting early BSA design features and had to be one of the prettier looking break barrel air rifles for it's time.

The prefix of CC tells me the rifle is made in the later half of the 1950's

The Cadet has a leather piston seal which in this case needed no oil to improve velocity, from what i remember from the chrony test there was no more the 25 FPS spread with any of the pellets i tested. From what i could see through the cocking slot both spring and piston appeared to be lightly lubricated, or at least it wasn't all dry and dusty. 

The Cadet has a one peice trigger and sear that hooks on to a central piston rod in the piston, how much of the sear that holds the piston rod can be adjusted by a screw in the slope at the rear of the action.

Without dimantling the rifle i had to looke at the plans on Chambers web site too find out this adjusted sear engagement.

 The stock is a one piece beechwood affair with a very long cocking slot, because it has a single piece cocking rod that is, like the rest of the rifle, very well made and solid.

Considering the length of the cocking slot, there was no movement in the stock, not one bit, non at all, zero, zilch.


The stock fits well to the action and is fixed with two screws at a 60 degree angle at the front of the action,

Screws made the old fashioned way, roled on the thighs of dusky Brummies.

and like the later Airsporter and Mercury the rear is a bolt that runs through the pistol grip and screws into the rear section of the action. 

The reat bolt. Like it say's on the tin, bolts the rear on.

The Cadet has some weight to it for its size as i said before and although it is pretty old there is no movement between the forks, or anywhere at all come to think of it, from wear over the years.


I have no idea if a pin or a bolt holds the forks around the breech, it's still a solid fit though.

There are only open sights on this rifle and has no scope rail, because scopes just weren't commonly used in the 50's. The front sight is a bead on top of a concave ramp that sits in a dovetail on the tip of the barrel, left to right adjustment could be achieved by tapping the sight along the dovetail.

The front sight had already been adjusted and was fine, notice it hangs over too the right.


From this angle the dove tail is more noticable.

The rear sights that sit on top of the breech block are real old school and tend to be found on most early 1900's air rifles, they adjust up and down only by spinning a firm horizontal thumb wheel. This allows a plate with a V notch on top to move vertically in its frame, score marks on the side of the frame and plate help keep track of adjustments


These sights were perfectly fine in the 50's and still perform well today.

The trigger and guard are very slim but also pretty solid due to the fine quality of the metal used to build it. The trigger appears to have a light too mediun release and along with the angle of the pistol grip and the low combe on the buttstock, found it very comfortable too shoot with satisfying results.

The trigger guard design is a tried and tested BSA design and can be found on later Meteors

Low recoil, trigger release, weight, and pretty nifty old school sights all added up to some good off hand accuracy. 7 out of 9 Geco wadcutters made one impressive one cm ragged hole and JSB Exacts appeared to spred vertically, however they were the only two pellets i tried at the time.

I reckon Superdomes would do well in this air rifle, should get some really.

When all is said and done, the BSA Cadet is an awesome back yard plinker that reeks of nostalgia from a time we can only imagine and most likely never happened.

This rifle came to me in good condition internally and out, and as a plinker did not need any attention apart from a little oil and wire wool for the matal work. It's fun and definately gets a thumbs up.

All the best,

Wing Commander Sir Nigel Tetlington-Smythe 

Tuesday, 6 September 2016

Lee's Mk II .177 Innova



Lee's .177 Innova

It would appear that i'm getting myself a bit of a rep for fixing up old Innova's for people and each time i find something new that i've not come across before. Lee got in touch with me saying that he could not get any power out of his .177 MkII Innova after trying to follow some of my guidelines, i offered to take a look at it and a few days later a rather splendid looking example of an Innova came through the post.

exciting, what's in the box.

Oh, it's an Innova in bits.

It was in many bits where he had tried to fix it and a few of the parts were damaged through wear and tear with the odd part missing, the arms of the front sight post had snapped off

This is not good, but will do for now.

 and the circlip for holding the pump arm pin was missing. 

I'm gonna have to make a circlip for this.

Originally this was Lee's rifle and he had let a friend have it and from then on it had passed on through a few other people till it came back to Lee, it would appear that a few of these people have been messing about with it in a not to kind of manner since then.

Still the same Innova

Lets face it  the Innova is mostly polymer/plastic and after 25 odd years things are going to wear out, get stressed, chip and snap off, work loose and bend. Especially if a few off those people think it's a cool idea to ramp the power up, when really it will recieve a hell of a lot less sress if you only pump it 8/9 times to get 12 ft/lb and not 15 times to get 16 ft/lb. 

The tension on that spring will decide if it's under power, just leagal, or over the top.

It's certainly not the same gun Lee remembers from his youth, but with a bit of TLC and some crafty bodging it could be pretty damded close


There you go, MkII Innova.


MkII's have the safety catch.

MkII's also have a butt pad.

The power was no problem to fix as i adjusted the pump rod to the maximum reach. oiled the pump head, and with five pumps it was letting out a satisfyingly loud crack, however i could still put in 15 pumps without the blow off valve kicking in. I also left three pumps of air in the rifle overnight which had leaked out come the morning time, so looks like a good old fashioned overhaul is required.

When i stripped it again i noticed that oil had leaked past the exhaust valve body O ring so that one needed replacing, 

Yep, had to replace some O rings here.

i also stripped the valve and replaced the O ring between the Valve and firing pin housings thinking that that could be the cause of the slow leak. Everything else inside looked fine which was what Lee had done himself, there was still a leak on putting it back together but much, much slower.

Seeing as i had a set of firing pin seals i removed the firing pin,

Bolt assembly.

so replacing the seals would let me know that all the power from pumping was hitting behind the pellets.
 
New seals fitted.

Using a pipe wench, 10 and 14 mm spanners, and some pliers i unscrewed the housing and pump head off the blow off valve, 

If you have to do this it's usually only the once, after that finger adjustment is all that's needed

out came the spring  and valve pin was removed easily with a small pair of needle nose pliers. 

Someone else has been messing about here, looks like somethings missing.

Inside the valve housing was a brass sleeve which screwed into the inner wall and held the blow off valve seal in place tightly, lining up with the underside of the pumphead there were two knotches so i could cut and shape a flat bit of metal to act as a screwdriver. It all came out with years of crap and oil and gunk but looked in good knick all the same, and sure enough when it went back together it worked which in my opinon was a result, praise be Saint Jezzer.
 
Down to all the basic bits


The head of the valve pin has a cup shape which looks like it would seat a 4.5 mm ball bearing,

Reckon a ball bearing should fit in there, but some sad hat must of lost it way back.

so i added a ball bearing as it would seat better against the blow off seal and the air pressure would blow off at pretty much the same each time.

Now that looks like it should work better.

Putting the pump arm back together now left me with getting the the blow off valve to release around 11.5 ft/lb, minute adjustments on the spring pressure where needed.First adjust the tension on the blow off valve spring,

!001 minute adjustments.
  

then adjust the slack on the other end of the valve

1001 minute corrections

 198 mm seems the ideal length for the whole pump rod assembly.

I really couldn't be arsed to check this a 1001 times.

If it's too short the the pump arm doesn't lock in place and hangs down,
 
So sometimes this happened.

if its close to right then it will lock in place.
 
But mostly not.

It sort of went too low, too low , too low, shit too high, still too high all the first afternoon.

Why did it take so long that afternoon?

But for some reason on the second afternoon it took no time at all, sure had me puzzled.


2nd afternoon took no time at all.


So there you go, one MkII Innova fixed to the best of my abilities. To get it nearer perfect Lee will have to invest in a new front sight unit and a stock screw and brass collar as they are fairly worn, but for now i got the stock on tight with the use of a small washer.

With the aid of a little washer the action sat firmly in the stock.

Remember boys and girls, old Innova's never die they just get sent to me to bodge, fix, and generally get loving treatment.

TTFN.

Best wishes, Wing Commander Sir Nigel Tetlington/Smythe. 


 P.S. Remember to remove all and any burrs from the inside of the compression tube as not only do they ruin seals, but they can make the pump rod awkward to to remove and replace.

It's boring work but it saves you so much hassle in the long run.