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Alstone · Moderator & Site Supporter

Can anybody tell me whether a QB78 is cocked by the bolt or trigger, and if by the trigger as anybody converted one to work off the bolt.

AL

StevieLaner7777 · Moderator

Hi Al

The QB78/XS78 is cocked by the bolt, When the bolt is pulled back it will engage with the hammer latch and when the bolt is pushed to the forward posision ("Home" posision) it will charge the hammer spring. All the trigger does is release the hammer.
This makes for a very smooth and light trigger action.

Hope this helps!

Stevie Thumb Up!

Alstone · Moderator & Site Supporter

Cheers Stevie

I was reading on another site that a QB was cocked by the trigger, which I though was rather strange, anyway thats sorted that out. Thank-You

What diffrence do you think it would make if I choped 5 or 6 inches of the barrel making a QB into a carbine, do you think it would stand it ?.

AL

StevieLaner7777 · Moderator

Hi Al

I'm not sure what those guys on that other site must be smoking but by the sounds of it, It's pretty strong! Hammer Head

OK, IMO I think chopping the barrel down on any Airgun would dramatically reduce the proformance of it, as the barrel is the most important part of any gun, it provides the Power, Velocity and Accuracy to the projectile, So cutting this part down would also be cutting all of these factors by the percentage of the barrel that is cut.

Though if you were to do this as well as tuning the valve you could make a very shot effeicient QB78, Still with only limited power yet lots of shots out of two 12g Co2 caplets.

So really it's up to you, But I don't think I will be doing it too soon.

Stevie Thumb Up!

Alstone · Moderator & Site Supporter

Stevie yes I realize that the Performance would be down, what I should have asked was how many turns of the rifling is there on the barrel ?, if I can chop a few inches off and still retain at least one and a quarter turns, things should be allright.

Can you identifiy this gun, I think it is a WWll US M1 Carbine, but I'm not sure, I found the photo on the net but no title, I had a thought that a cut down QB with a new stock and a bit of cosmetic surgery would look nice as an M1

Ha Ha here's the missing image Embarassed

AL

StevieLaner7777 · Moderator

Hi Al

Sorry I'm away from home at the moment, So I don't have access to my Bro's QB78 or manual, So I don't know at the moment though I will look around to see if anyone has posted the specifications anywhere on the net. All I can remember about the barrel is that it is 54.6 cm long and is 14.20mm OD (Though this is not what your asking for, Sorry).

About if I can identifiy the mystery gun, If you could post the image of it that you found, I think I or anyone else would be able to tell you, I would definatly have to see the image first though before I could give you a positive identification.

Stevie Thumb Up!

StevieLaner7777 · Moderator

Hi Al

OK now that you have added the image to your post, I agree with you it's a M1 Carbine, though some of the features look a bit different one for example would be the mag, it looks to be smaller than the normal 15x.30cal, So I'm predicting that it is a variant of the M1 Carbine probably the M1A2 though all of the M1 varients used .30cal rounds so the mag size is a bit confusing so I'm not entirly sure on which version it is, I will have another look around tomorrow.

Also I haven't found any info on the QB78 rifling yet, I looked though loads of sites but just didn't see anything about the rifling twist rate, Strange!
If I see any info on it I will let you know.

Stevie Thumb Up!

broommaster2000 · Moderator

It's not an M1. It's a .22 Rimfire Erma EM1. It's a replica, so to say.

StevieLaner7777 · Moderator

Ah! Cheers Broom!

Thats difinatly it! .22LR explains the small angled magazine.

Here's an Image of the Erma EM1 to compare:

M1 Carbine:

Stevie

Alstone · Moderator & Site Supporter

Cheers Broom/Stevie
I thought it might be an M1 converted to .22, I didn't realize it was a replica.

OK so what air rifle would cut down and fit in to an M1 stock ?, as I quite like the look of an M1, and the only thing I can think of is a 1077, the QB78 which I have been looking at would be to big from the trigger to the top of the breech, plus it would need to be multi-shot.

AL

Alstone · Moderator & Site Supporter

To get some idea what the diffrence between a 1077 and a QB78, I pasted them on to a M1 Stock, I think the 1077 looks better.

QB78

1077

AL

AirGunEric · Site Admin

I think the 1077 definitely looks more "streamlined".

broommaster2000 · Moderator

Alstone · Moderator & Site Supporter

Very nice Broom, thats something like I'm looking for, but more of a carbine, I'm trying to keep the cost down so I'm back to the QB78, which lends itself quite well to a bolt action carbine.

I have done a mockup of what I think it would look like, Get rid of the back sight make a new one for the back of the breech, change the front sight for a M1 type and shorten the barrel.

AL

broommaster2000 · Moderator

It's hard to get those scales right. Better put an m1 carbine next to a QB78 first.