Interesting little tool for the BF-109?

[Scherf]

Y'all are good.

August '41 - I take it that's an F?

[Devil 505]

you would be correct.

[Wagger]

CptA spoken like a true tanker or Master Gunner.

[CptA]

Thx, I spent 22 of my 31 years of service on tanks.

I started out on M48A5s, moved up to M60s, then M60A1s, M60A3s (my favorite from a Commander/Gunner perspective), and finally M1s and M1IPs.

After that it was all staff time at Bn,  Bde, and Div level.

A good Boresite, Sync, and Screening has always been the key to an effective trip downrange on the Tank Tables.

Like any well-drilled task it gets to be second nature, but you have to be carefull to prevent your crew from getting lazy and taking shortcuts...thats what manuals (and good NCOs) are for.

Steel on Target!

CptA

[AHTbolt]

CptA I started in M60A3 and ended in M1A1s was my BN master gunner and shot 995 on tank table 8 was a great day for my crew. Oh never ever do an MRS update you will never hit anything, iv been out 10 years now and I could still bore sight a tank.

[ozrocker]

CptA, he's not a peelot. They had gull wing insignia on collars.
More than likely an Armament Specialist.




                                                                                                               Oz

[Krusty]

could we please get that skin 

er.... okay.....

[Volron]

could we please get that skin 

er.... okay.....

(Image removed from quote.)
(Image removed from quote.)

I do believe that is a "Wish Granted". 

[lyric1]

I do believe that is a "Wish Granted". 

[bustr]

Motorkanon were locked into the DB60X/Jumo-213E and fired level to the engine airscrew shaft line through the hollow airscrew shaft. Otherwise your round would either explode or go flying off in any direction but at the target.

The Reflexvisior gunsight was adjusted so your line of sight (visier linie) angled down over the nose of the 109 and intersected 417cm drop at 700M for a 15mm/20mm canon and 430cm drop at 500M for a 30mm canon. Not the cannon angled inside of the engine to make the round drop center on the gunsight or target. The hood MG and gondola guns could be adjusted for convergence and point of impact patterning. Everything was adjusted to give a rough 30-40cm high area of patterning between 200 and 300 meters that followed loosely the fixed trajectory of the motorkanon.

I will assume with the Ta152-H the Revi gunsight line was adjusted down with the MK108 trajectory like in the 109 family while the two wing root Mg151/20 were adjusted to pattern with it between 200M and 300M similare to the gondola patterning in 109's.

MG151/20 Motorkanon
28cm drop at 250M
210cm drop at 400M
Drops off drasticly after 400M. 300+cm(10ft) by 500M

MK108 30mm Motorkanon
120cm drop at 250M
338cm drop at 400M
Drops of really drasticly after 400M. 550+cm(18ft) by 500M

Russian autocanon were locked down between the cylanders in the Yak family and so was the HS.404 moteur-canon in the French  Dewoitine D.520.

[Big Rat]

Great post CptA , very informative

 
BigRat

[Krusty]

Bustr... 30mm is barely more than an inch. The exit of the blast tube is at least 3 inches. You can have a lot of leeway regarding convergence with that kind of free space. It would not have hit anything unless you moved it way out of standard alignment.

[bustr]

The 109 armerors manuals say the MG151/20 and MK108 are "locked" parallel to the shaft. All of the barrel adaptors make sure the barrel is centered into the shaft and locked down with four bolts. That sighting  device is so the person sighting from the barrel can see the impact diagram and round patterning and note the patterning of the motorkannon, MG and gondola (if mounted) in refrence to standardised patterns for either 50 meter or 100 meter firing ranges. At those ranges the (visier linie) line of sight for the Refelxvisior is adjusted so the piper center lines up at a specific distance below the IP of the motorkanon for each cannon type.

The blast tube or hollow airscrew tube is that large of a diameter because the high speed spin induced into the mine rounds to unlock the fuse can cause random fliers. I seem to remember some of the early MK108 testing with G6 at Rechlin had a problem with the mine rounds hitting the inside of the tube. That could be why they changed fuse types from the AZ 1587 standard ACK-ACK fuze with an assymetrical safety to the ZZ 1589 with six symetrical ball berings and self detonation after traveling 700-1000M.

Find any Bf109 manual on the internet and translate the armerors section for mounting the motorkanon. They all say it's locked in and fires straight through the hollow airscrew shaft. In the back of the manuals you will find the impact forms that the sighting device looks at from the perspective of the primary wheapon on the Bf109. You can find pictures of the russian cannons bolted down to the top of the block firing through the reduction gearing and the same with the Dewoitine D.520's engine.

[nrshida]

bustr is right, the motor cannons of all of the Bf/Me109s were fixed.

[Krusty]

The 109 armerors manuals say the MG151/20 and MK108 are "locked" parallel to the shaft. All of the barrel adaptors make sure the barrel is centered into the shaft and locked down with four bolts. That sighting  device is so the person sighting from the barrel can see the impact diagram and round patterning and note the patterning of the motorkannon, MG and gondola (if mounted) in refrence to standardised patterns for either 50 meter or 100 meter firing ranges. At those ranges the (visier linie) line of sight for the Refelxvisior is adjusted so the piper center lines up at a specific distance below the IP of the motorkanon for each cannon type.

The blast tube or hollow airscrew tube is that large of a diameter because the high speed spin induced into the mine rounds to unlock the fuse can cause random fliers. I seem to remember some of the early MK108 testing with G6 at Rechlin had a problem with the mine rounds hitting the inside of the tube. That could be why they changed fuse types from the AZ 1587 standard ACK-ACK fuze with an assymetrical safety to the ZZ 1589 with six symetrical ball berings and self detonation after traveling 700-1000M.

Find any Bf109 manual on the internet and translate the armerors section for mounting the motorkanon. They all say it's locked in and fires straight through the hollow airscrew shaft. In the back of the manuals you will find the impact forms that the sighting device looks at from the perspective of the primary wheapon on the Bf109. You can find pictures of the russian cannons bolted down to the top of the block firing through the reduction gearing and the same with the Dewoitine D.520's engine.

I wasn't exactly refuting "it was locked" just "it would hit the tube wall if so" -- there's enough leeway was my point. Actual practice is another matter.