±Recent Visitors

Recent Visitors to Com-Central!

±User Info-big


Welcome Anonymous

Nickname
Password

Membership:
Latest: HighestAce
New Today: 0
New Yesterday: 0
Overall: 6648

People Online:
Members: 0
Visitors: 317
Total: 317
Who Is Where:
 Visitors:
01: Home
02: Community Forums
03: Statistics
04: Photo Gallery
05: Member Screenshots
06: Downloads
07: Photo Gallery
08: Photo Gallery
09: Home
10: Community Forums
11: Community Forums
12: Community Forums
13: Statistics
14: Community Forums
15: Photo Gallery
16: Photo Gallery
17: Community Forums
18: Photo Gallery
19: Community Forums
20: Member Screenshots
21: Photo Gallery
22: Community Forums
23: Community Forums
24: Community Forums
25: Home
26: Community Forums
27: Home
28: Community Forums
29: Home
30: Community Forums
31: Community Forums
32: Home
33: Photo Gallery
34: Home
35: Community Forums
36: Community Forums
37: Community Forums
38: Community Forums
39: Community Forums
40: Community Forums
41: Community Forums
42: Community Forums
43: Home
44: Community Forums
45: Home
46: Downloads
47: Home
48: Community Forums
49: Community Forums
50: Community Forums
51: Community Forums
52: Community Forums
53: Community Forums
54: Community Forums
55: Member Screenshots
56: Home
57: Community Forums
58: Community Forums
59: Statistics
60: Member Screenshots
61: Community Forums
62: Community Forums
63: Photo Gallery
64: Community Forums
65: Community Forums
66: Community Forums
67: Community Forums
68: Photo Gallery
69: Home
70: Home
71: Member Screenshots
72: Community Forums
73: Home
74: Community Forums
75: Community Forums
76: Community Forums
77: Community Forums
78: Member Screenshots
79: Community Forums
80: Community Forums
81: Community Forums
82: Community Forums
83: Community Forums
84: Community Forums
85: Community Forums
86: Community Forums
87: Community Forums
88: Home
89: Photo Gallery
90: Home
91: Home
92: Community Forums
93: News
94: Home
95: Home
96: Community Forums
97: Community Forums
98: Community Forums
99: Community Forums
100: Downloads
101: Community Forums
102: Community Forums
103: Community Forums
104: Community Forums
105: Community Forums
106: Community Forums
107: Community Forums
108: Community Forums
109: Photo Gallery
110: Home
111: Community Forums
112: Community Forums
113: Home
114: Photo Gallery
115: Community Forums
116: Community Forums
117: Tell a Friend
118: Community Forums
119: Photo Gallery
120: Photo Gallery
121: Home
122: Community Forums
123: Community Forums
124: Community Forums
125: Downloads
126: Community Forums
127: Home
128: Community Forums
129: Home
130: Community Forums
131: Photo Gallery
132: Home
133: Community Forums
134: Downloads
135: Community Forums
136: Member Screenshots
137: Home
138: Community Forums
139: Your Account
140: Photo Gallery
141: Home
142: Downloads
143: Photo Gallery
144: Your Account
145: Home
146: Community Forums
147: Community Forums
148: Downloads
149: Statistics
150: Home
151: Downloads
152: Photo Gallery
153: Home
154: Home
155: Community Forums
156: Community Forums
157: Community Forums
158: Community Forums
159: Downloads
160: Photo Gallery
161: Community Forums
162: Member Screenshots
163: Photo Gallery
164: Community Forums
165: Home
166: Home
167: Community Forums
168: Community Forums
169: News Archive
170: Community Forums
171: Home
172: Member Screenshots
173: Home
174: Community Forums
175: Community Forums
176: Home
177: Community Forums
178: Community Forums
179: Community Forums
180: Community Forums
181: Photo Gallery
182: Community Forums
183: Home
184: Member Screenshots
185: Community Forums
186: Community Forums
187: Home
188: Community Forums
189: News
190: Community Forums
191: Downloads
192: Community Forums
193: Community Forums
194: Community Forums
195: Community Forums
196: Community Forums
197: Photo Gallery
198: Community Forums
199: Home
200: Photo Gallery
201: Member Screenshots
202: Your Account
203: Home
204: Home
205: Community Forums
206: Home
207: Community Forums
208: Photo Gallery
209: Home
210: Community Forums
211: Home
212: Community Forums
213: Downloads
214: Community Forums
215: Your Account
216: Community Forums
217: News
218: Downloads
219: Community Forums
220: Home
221: Member Screenshots
222: Community Forums
223: Home
224: Community Forums
225: Community Forums
226: Community Forums
227: Home
228: News Archive
229: Community Forums
230: Community Forums
231: Community Forums
232: Home
233: Community Forums
234: Home
235: Home
236: Your Account
237: Community Forums
238: Community Forums
239: Home
240: Community Forums
241: Photo Gallery
242: Home
243: Community Forums
244: Community Forums
245: News
246: Photo Gallery
247: Photo Gallery
248: Home
249: Home
250: Downloads
251: Home
252: Home
253: News Archive
254: Home
255: Community Forums
256: Community Forums
257: Community Forums
258: Community Forums
259: Community Forums
260: Community Forums
261: Community Forums
262: Community Forums
263: Downloads
264: Home
265: Home
266: Community Forums
267: Photo Gallery
268: Photo Gallery
269: Community Forums
270: Community Forums
271: Community Forums
272: News Archive
273: Community Forums
274: Community Forums
275: News
276: Community Forums
277: Member Screenshots
278: Home
279: Community Forums
280: Home
281: Community Forums
282: Community Forums
283: Community Forums
284: Home
285: Your Account
286: Photo Gallery
287: Community Forums
288: Community Forums
289: Photo Gallery
290: Community Forums
291: Community Forums
292: Community Forums
293: Home
294: Community Forums
295: Community Forums
296: Community Forums
297: Community Forums
298: Community Forums
299: Community Forums
300: News Archive
301: Community Forums
302: Community Forums
303: Community Forums
304: Downloads
305: Community Forums
306: Home
307: Downloads
308: Photo Gallery
309: Your Account
310: Community Forums
311: Downloads
312: News
313: Photo Gallery
314: Home
315: Downloads
316: Community Forums
317: Community Forums

Staff Online:

No staff members are online!
M103 Tank Ammo (120mm)
The AFV ASSOCIATION was formed in 1964 to support the thoughts and research of all those interested in Armored Fighting Vehicles and related topics, such as AFV drawings. The emphasis has always been on sharing information and communicating with other members of similar interests; e.g. German armor, Japanese AFVs, or whatever.
Go to page 1, 2  Next
Post new topic    Reply to topic    Printer Friendly Page     Forum Index ›  AFV News Discussion Board

View previous topic :: View next topic  
Author Message
Jinx
Power User

Offline Offline
Joined: Jan 24, 2006
Posts: 186
Location: Canada
PostPosted: Fri Mar 10, 2006 12:45 pm
Post subject: Re: M103 Tank Ammo (120mm)

Assuming that is an APFSDS projectile on the far left, is the short cartridge the one that launches it? Is there anything that goes in between the two when they are loaded into the breech?
Back to top
View user's profile
bsmart
Power User

Offline Offline
Joined: Jan 23, 2006
Posts: 2523
Location: Central Maryland
PostPosted: Fri Mar 10, 2006 1:43 pm
Post subject: Re: M103 Tank Ammo (120mm)

Just a guess but I would assume they rechambered the tank mounted 120mm gun to use a shorter case than the 120mm AA gun. This would be desirable because of the cramped space in a tank turret. With newer more poereful propellent a shorter case could still provide a high MV.

Is the round on the left a HEAT round? I don't think APFSDS was around when the 120mm gunned M103 was in service was it? The shape of the front end of the round looks like a HEAT round with the stand off nose that was common in that era. I know it is desirable for a HEAT round not to spin so I would guess that the fins were ther to stabilize the round instead of using the rifling in the gun barrel

again the above is just my guess as to what and why.

_________________
Bob Smart ([email protected])
Back to top
View user's profile Send e-mail
mike_Duplessis
Power User

Offline Offline
Joined: Jan 24, 2006
Posts: 236

PostPosted: Fri Mar 10, 2006 1:59 pm
Post subject: Re: M103 Tank Ammo (120mm)

As bsmart said, the projectile to the far left is a HEAT round with a stand-off probe. That's what HEAT rounds have looked like for about 40 years now - even Russian rounds!
An explanation for the shorter cartridge case may be that the HEAT round used a smaller charge than the AP. They usually do. The Russian 125mm gun with its split rounds gets around that problem by packing a portion of the propellant with the APFSDS round itself, so both the HEAT and AP can share the same charge. The dramatically different case size for the 120mm may have been so the loader couldn't accidentally mistake a big AP charge for the HEAT charge. For all I know firing a HEAT round with a full AP charge may have been dangerous! ...Just a guess on my part.


Last edited by mike_Duplessis on Fri Mar 10, 2006 2:02 pm; edited 1 time in total
Back to top
View user's profile
Jinx
Power User

Offline Offline
Joined: Jan 24, 2006
Posts: 186
Location: Canada
PostPosted: Fri Mar 10, 2006 2:00 pm
Post subject: Re: M103 Tank Ammo (120mm)

Oops, my error. That is a HEAT round and not an APFSDS. (Hanging head)

I still am having trouble picturing how this works when separately loaded. Does the loader ram in the HEAT round first, then ram in the cartridge afterward? It doesn't seem as if it would be easy to ram in the projectile by hand, what with the fins and all. Any help with that?
Back to top
View user's profile
Dontos
Power User

Offline Offline
Joined: Jan 24, 2006
Posts: 3436
Location: Vine Grove, KY
PostPosted: Fri Mar 10, 2006 2:07 pm
Post subject: Re: M103 Tank Ammo (120mm)

- Jinx
Oops, my error. That is a HEAT round and not an APFSDS. (Hanging head)

I still am having trouble picturing how this works when separately loaded. Does the loader ram in the HEAT round first, then ram in the cartridge afterward? It doesn't seem as if it would be easy to ram in the projectile by hand, what with the fins and all. Any help with that?


Its all one piece ammo.

The image has the rounds seperated to show the actual projectiles size.

The loader just removes the round from the rack swings it around (or flips the round) and slams it in the chamber. Simple process.

As for interior space, I've been in an M103 on several occasions. I felt it was hugely 'roomie' as compared to the Abrams.

The TCs position being an amazing sub-area in the rear of the turret. I was envious of all the places to 'stow' personal convience items (ie 'munchies' and the such...) LOTTA ROOM!!

_________________
"Gonna hold my breath until Armor returns home..."
Back to top
View user's profile Send e-mail Visit poster's website AIM Address Yahoo Messenger Photo Gallery
mike_Duplessis
Power User

Offline Offline
Joined: Jan 24, 2006
Posts: 236

PostPosted: Fri Mar 10, 2006 3:20 pm
Post subject: Re: M103 Tank Ammo (120mm)

The 120mm ammo thing is confusing because some guns (the oscillating turret designs) used one-piece rounds and some used split rounds for the same gun type. The reason why the rounds were split were partially to do with unweildy length, but also to do with their weight. Load 8 or 9 70+ pound one piece AP rounds in quick succession and you'll be ready to lie down for a nap! It seems round weight doesn't usually exceed 50 lbs. if they're going to be manually loaded (artillery doesn't count).

Maybe Marine M103s were different and used the 1-piece rounds because jar-heads are just more manly than the rest of us. Wink

I'd swear that either Conqueror or M103 (or maybe just the prototype) used two loaders in an efort to speed up ROF. But I can't recall which it was.
Back to top
View user's profile
Roy_A_Lingle
Power User

Offline Offline
Joined: Jan 24, 2006
Posts: 1997
Location: El Paso & Ft Bliss, Texas
PostPosted: Fri Mar 10, 2006 8:53 pm
Post subject: Re: M103 Tank Ammo (120mm)

Hi Folks!

Don't forgot, the M-103 with all it's room had TWO loaders.

Where is OldTop when we need him. He would know what type of ammo the M-103 used.

Sgt, Scouts Out! Smile

_________________
"You can never have too much reconnaissance."
General G.S. Patton Jr.


Last edited by Roy_A_Lingle on Sun Mar 12, 2006 6:23 pm; edited 1 time in total
Back to top
View user's profile Send e-mail
Dontos
Power User

Offline Offline
Joined: Jan 24, 2006
Posts: 3436
Location: Vine Grove, KY
PostPosted: Fri Mar 10, 2006 9:26 pm
Post subject: Re: M103 Tank Ammo (120mm)

I haven't 'talked' him since the switch over...

_________________
"Gonna hold my breath until Armor returns home..."
Back to top
View user's profile Send e-mail Visit poster's website AIM Address Yahoo Messenger Photo Gallery
tankmodeler
Power User

Offline Offline
Joined: Jan 25, 2006
Posts: 42
Location: Ontario
PostPosted: Sat Mar 11, 2006 3:33 pm
Post subject: Re: M103 Tank Ammo (120mm)

The 103 used two-piece ammo for all rounds and had two loaders in the monsterous turret. The Conq was the same as it useed the same gun.

I must say I find it strange that the HEAT round had a shorter case. I know the charge in the case was smaller because the velocity of the HEAT round doesn't affect it's penetration, but most breech designs seal the breech from the propellant gasses by the mouth of the case expanding under the pressure and sealing at the forward lip of the case. If that lip is in two places, you have to make bloody sure that two places in the breech are machined precisely enough to do the job and that the wear and tear of normal firing doesn't degrade that second location so that gasses bypass the block and get back into the turret. The shorter case would also mean that the normal breech surface would be exposed to the gasses from the shorter HEAT casing. Very bad for the metal and for the abilitty to seal the breech.

Makes no sense. I'm not sure that it could be done for an operational vehicle.

Are we sure the casing hasn't been cut down and then mounted inthe display? Sometimes displays are made up from parts laying around or refurbished from older displays and are not necessarily totally accurate. Just a thought.

Paul Roberts

_________________
Paul Roberts
President
Armor Modeling and Preservation Society
Back to top
View user's profile
bsmart
Power User

Offline Offline
Joined: Jan 23, 2006
Posts: 2523
Location: Central Maryland
PostPosted: Sun Mar 12, 2006 12:41 am
Post subject: Re: M103 Tank Ammo (120mm)

I was at Aberdeen today and another volunteer who is more interested in ammunition than tanks or small arms was there (He is a professional EOD guy). I asked him if he knew anything about this but couldn't bring up a computer where we were. He said he had recently found out about the difference in the two 120mm cases and there is a reason. He is going to dig out the information on it and leave it at the museum for me. When I get the information (It may be a few weeks) I'll pass it on.

Where was the display?

_________________
Bob Smart ([email protected])
Back to top
View user's profile Send e-mail
Doug_Kibbey
Power User

Offline Offline
Joined: Jan 23, 2006
Posts: 4678
Location: The Great Satan
PostPosted: Mon Mar 13, 2006 2:02 am
Post subject: Re: M103 Tank Ammo (120mm)

- Roy_A_Lingle
Hi Folks!

Don't forgot, the M-103 with all it's room had TWO loaders.

Where is OldTop when we need him. He would know what type of ammo the M-103 used.

Sgt, Scouts Out! Smile


You got me curious, so I searched the old forum and sent "oletop" an email just today...lessee' what happens....
Back to top
View user's profile Visit poster's website Photo Gallery
mike_Duplessis
Power User

Offline Offline
Joined: Jan 24, 2006
Posts: 236

PostPosted: Tue Mar 14, 2006 1:33 pm
Post subject: Re: M103 Tank Ammo (120mm)

I finally dug out my copy of Hunnicutt's "FIREPOWER" (yes, I own a rare precious edition of FIREPOWER) and here's what I found on the rounds:

The complete AP-T M358 (two piece) round weighted a hefty 107 pounds. The shot alone weighed 50.85 pounds. AP and training shells used the propelling charge M46, which used a case 34.7" long (the shot was 18.76" long, making the total round a bit under 4 1/2 feet long").

The HE and WP shells used propelling charge T21E1, which also had a case 34.7" long.

The HEAT round M469 pictured above didn't come about til the Marine upgrade of the M103 in the early 60s. The HEAT shell was 29 inches long. The propelling chage that went with it was just 26.35" long. Special round stowage had to be installed for these odd-size rounds.

To show the difference between the long and short propelling charges, the AP-T M348 round had a muzzle energy of 4,318 foot-tons. The HEAT shell's muzzle energy was just half that at 2,184 foot-tons.
Back to top
View user's profile
Jinx
Power User

Offline Offline
Joined: Jan 24, 2006
Posts: 186
Location: Canada
PostPosted: Tue Mar 14, 2006 8:07 pm
Post subject: Re: M103 Tank Ammo (120mm)

In comparison, does anybody know right off the weights of the various rounds for the 120mm Rheinmetall gun in the Abrams and Leopard 2?
Back to top
View user's profile
mike_Duplessis
Power User

Offline Offline
Joined: Jan 24, 2006
Posts: 236

PostPosted: Tue Mar 14, 2006 9:07 pm
Post subject: Re: M103 Tank Ammo (120mm)

I want to say the current 120mm gun rounds weigh about 50 pounds more-or-less. The benefit of not using an old-fashioned solid AP shot or a brass case. Someone who knows better should confirm or deny this, though.
Back to top
View user's profile
Dontos
Power User

Offline Offline
Joined: Jan 24, 2006
Posts: 3436
Location: Vine Grove, KY
PostPosted: Tue Mar 14, 2006 10:55 pm
Post subject: Re: M103 Tank Ammo (120mm)

Mike

120mm HEAT(M830:HEAT-MP-T) 53.4 lbs
120mm SABOT(M829A1: APFSDS-T) 46.22 lbs

As referenced from 'M1 Abrams at War' by Michael Green

_________________
"Gonna hold my breath until Armor returns home..."
Back to top
View user's profile Send e-mail Visit poster's website AIM Address Yahoo Messenger Photo Gallery
Display posts from previous:   
Post new topic    Reply to topic    Printer Friendly Page    Forum Index ›  AFV News Discussion Board
Page 1 of 2
All times are GMT - 6 Hours
Go to page 1, 2  Next



Jump to:  


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You cannot download files in this forum