Article by Doug Chaltry; last updated 22 February 2017

The scans below show each rotor shield side-by-side, making clear which kits actually have the most scale-accurate pieces in this line-up. Below the rotor shield comparison, I provide comparison scans of the 105mm gun barrels.

Rotor Shields

It hasn't been easy coming up with accurate measurements for these parts, since I have very few drawings of the 105mm gun mount, and the ones I have are contradictory or of questionable accuracy. Based on the best drawings I have, it appears that the rotor shield should be 14.4mm wide without the bolted rim (which was used for attaching a canvas cover to the gun shield), or 14.7mm with the rim. Dragon is the only kit that has this feature. Most, if not all, 105mm Shermans had this canvas dust cover installed, so you really should add it to those kits below that don't have one.

Once again, I should add that although the table below shows that most of the pieces are undersized, they are pretty close to accurate. At this small size, I think that most of them will look perfectly fine once built.

Picture	Manufacturer	Size	Comments
	Dragon M4A3 (105)	13.5mm	The Dragon kits have overall the best detail and contours, though they are both a bit small. This early M4A3 (105) VVSS kit is smaller than the following kit. These are the only pieces here that have the bolted rim for attaching a canvas dust cover for the gun mount.
	Dragon M4A3 (105) HVSS	14.0mm	Dragon improved upon the shield for this later kit, enlarging the piece a small amount, though it is still a bit too narrow. Has the bolted rim for the canvas cover.
	Eduard	13.2mm	The Eduard shield is the smallest of the plastic shields, and is probably the only plastic piece I would not use without trying to improve it a bit. Perhaps adding some plastic card to the outer edges and contouring it to shape with a little putty would do the trick. The gunsight aperture needs to be opened up.
	HäT	14.5mm	The HäT kit is very good for a wargaming kit, and it's the plastic part most accurate in size. Drill open the apertures and you'll have a very nice shield.
	UM	14.1mm	UM's rotor shield lacks the cast surface texture of the Dragon parts, though it's a pretty decent piece itself.
	Al.By	12.9mm	Al.By's shield is one of the first resin pieces provided to us long ago, but unfortunately is quite poor. It is the smallest one in the bunch, and is quite poorly shaped. The gun barrel was molded onto the shield as a single piece, so I cut it off for this comparison. You can see how misshapen the base of the gun barrel was.
	ARMO	15.0mm	As you can see, the ARMO barrel is molded integral with the shield, but this is such a nice piece that I didn't want to cut it off. Size is just a bit too wide, but nothing that can't be remedied. Very nice detail and cast texture as well. It looks like a copy of the MR Models shield.
	Commanders	13.9mm	Commanders' was also a very old conversion, and like the Al.By part, is not accurately shaped. It actually looks like a 17pdr shield to me and is totally incorrect for a 105mm shield. The shield was molded onto the turret face, so I removed it for this scan.
	MR Models	15.0mm	The MR Models rotor shield is the nicest shield in this review, but just a hair too wide. Sanding some resin from the sides should take care of that problem. It has a very nice cast texture and the detail is very good too.

Gun Barrels

I measured the length of the gun barrel that extends outside of the collar on the rotor shield. My references are inconsistent in the scale of their drawings, but the most reputable of them show that the correct measurement should be about 18.7mm. Most of the barrels are just a little bit too short, but will likely will look just fine when built.

Picture	Manufacturer	Size	Comments
	Dragon M4A3 (105)	18.2mm	The barrel from the Dragon kits (same piece comes in both kits) is a bit too skinny in my opinion. I think the fatter barrels of the other kits are more accurate.
	Dragon M4A3 (105) HVSS	18.2mm	The barrel from the Dragon kits (same piece comes in both kits) is a bit too skinny in my opinion. I think the fatter barrels of the other kits are more accurate.
	Eduard	18.0mm	Perhaps just a little bit too stout?
	HäT	18.6mm	Very nice shape and size.
	UM	18.4mm	Very nice piece.
	Al.By	17.9mm	Very poorly shaped and molded.
	ARMO	18.7mm	Copy of the MR Models gun already mounted in the shield.
	Commanders	15.3mm	Simply awful.
	MR Models	18.8mm	Perfect shape and length. This barrel is also sold as a separate item.
	Aber	???	Nicely shaped barrel, but it is a bit long. This piece needs to be recessed into the rotor shield just up to about 2mm behind that step in the barrel.