Install Mato 17pdr barrel into M4A3

[mozit]

Hi all.
I'd like to remove the barrel in my M4A3 105mm and replace it with the Mato 17pdr barrel. (yeah, I know the tank is all wrong for that but hey, for me it's just for fun)
I'm a total newb to this stuff, so feel free to call me naiive, but I thought it would just be a matter of pulling the original out and pushing the new one in.
It seems now it's not so easy ...............
I got the bottom of the turret off and, looking inside, it would seem the whole innards would have to be removed to get to the mantlet and gun so it can be removed.
Is this correct? Do I really need to take the whole thing apart just to replace the barrel?
Also, would the BB system still work with that barrel?
TIA
Peter

[Herr Dr. Professor]

OK: for starters, I cannot verify that the Mato 17-pounder will fit the HengLong Sherman. But there are oo-goo-gobs of wizards here on RCTW who can probably verify from experience. What is more, many have used the HengLong Sherman to build replicas of the British Sherman with its 17 pounder and big bustle turret. At the upper right on each page there is a search function. You might try various forms of "17 pdr." and see what you can find.

And I certainly understand your hesitation about disassembling the tank. I found out that it's not really so hard to dig out the guts of a turret if you go step-by-step and take a photo each step of the way. That way, when you reassemble--with the 17 pounder, I hope--you can refer to the photos. The learning by doing so is a good deal of the RC tank fun.

Of course, did I take photos the first time? But I learned and got all kinds of slivers under my fingernails reassembling the turret of a stubborn KV-2.

[tankme]

I don't believe the BB function can be retained as I think the interior diameter is less than 6mm.