Tzoli

ACCESS: Top Secret
Senior Member
Joined
1 February 2011
Messages
2,795
Reaction score
3,142
In Norman Friedman's US Amphibious Ships and Craft: An Illustrated Design History book (2002) mentions some interesting weapon systems:

In February 1983 the commandant of the Marine Corps asked the Defense Science Board to study the fire support issue.
...
The study was finally submitted on 4 April 1985 as the "Naval Surface Fire Support (NSFS) Improvement Study", and it was pointedly different from a study of Naval GUN fire support.
...
The future weapons considered by the study were a bomblet-carrying missile; an 8"/60 gun, lengthened to improve range compared to the earlier 8"/55, firing conventional, rocket assisted and extended-range (ramjet) ammunition; and the army missile system. Due to its long time to flight, the rocket-assisted projectile (RAP) round required a terminal seeker. A faster ramjet (with 70km range using solid fuel), then under navy development, did not contain a seeker. There was also interest in an anti-radar shell for the 8" gun. The gun might be an upgraded version of the earlier Mk 71 or a vertical loader.
...
The 8"/60 was assessed as the least expensive improvement but also the most marginal.
...
Several more exotic weapons were under development, including 5" and 155mm rail guns (electric guns) and a pulsed-power 5"/84 (hybrid solid-propellant gun). They did not figure significantly in the NSFS study, however.

The wikipedia article mentions a 155mm/70 "Combustion Light Gas Gun" but no mention of the 127mm gun. The 5"/84 Pulsed-Powered and 8"/60 conventional guns are also new to me!

Friedman also mentions fire support combat systems for an Iowa, the LPD-4 USS Austin, a Spruance and a Knox class vessel.

Did anybody hear about these weapon systems which seems not past through the earliest development stages? 5"/84 and the 8"/60 is quite interesting!
 
Also I've found mention of a 12"/70 gun considered for the MCLWG (Major Caliber Lightweight Gun) Project which never got beyond the proposal stage and which project produced the 8"/55 Mark 28/32 gun tested on USS Hull.

Another gun mention was from 1968, a 8"/39 for the then under development DX (Which became the Spruance class), abortive versions of the standard army 8" howitzer (2x was envisioned for the DX)
 
Last edited:
The article about the Fire Support Ships in the 1969/70 Jane's Fighting Ships mentions the planned armament of the FSS
Interesting to note that the 1972/73 JFS has almost exactly the same language but says three rather than four MCLWG. And several alternative configurations of that outfit (3 MCLWG, 2 Mk 66 5-in/54) show up as sketches in Friedman's US Amphibious Ships and Craft.
 
Well I meant gun mark not turret mark.
 
Well I meant gun mark not turret mark.

But Mark 71 was a mount designation, not a gun designation. There were two guns for the Mk 71 mount -- Mk 28 (a two-piece barrel) and Mk 32 (the planned production standard monobloc tube). A longer barrel would have just been a new barrel Mark with a different mount Mod.
 
In Norman Friedman's US Amphibious Ships and Craft: An Illustrated Design History book (2002) mentions some interesting weapon systems:



The wikipedia article mentions a 155mm/70 "Combustion Light Gas Gun" but no mention of the 127mm gun. The 5"/84 Pulsed-Powered and 8"/60 conventional guns are also new to me!

Friedman also mentions fire support combat systems for an Iowa, the LPD-4 USS Austin, a Spruance and a Knox class vessel.

Did anybody hear about these weapon systems which seems not past through the earliest development stages? 5"/84 and the 8"/60 is quite interesting!
8"/60 was the basic 8"/55 Mk16 brass cased autoloader from the Des Moines class with a 40" longer barrel, in a single mount turret.

5"/84 sounds like an electro-thermo-chemical gun, but that technology failed to live up to early promises of 50% increased power. More like 5% increase.
 
8"/60 was the basic 8"/55 Mk16 brass cased autoloader from the Des Moines class with a 40" longer barrel, in a single mount turret.
I'm not sure about that. Care to provide more info or source? I doubt they would re-use an 1940's design for a 1980's gun
 
I'm not sure about that. Care to provide more info or source? I doubt they would re-use an 1940's design for a 1980's gun
The 8"/55 Mk71 Major Caliber Lightweight Gun used a spare Des Moines class gun barrel in tests on USS Hull DD-945.


Your own reference says that the 8"/60 was "lengthened to improve range compared to the earlier 8"/55," and the only 8"/55 the US had in use was that Mk71.
 
I disagree. Never heard that a spare 8"/55 RF Mark 16 barrel (if any survived by that time which seems unlikely knowing that the USS Newport News's gun did not replaced) and wiki does not states a source for that info.

Navweaps site does not mention neither that the prototype gun was an older RF Mark 16 barrel:


There are plenty of missing gun marks between the Des Moines's RF Mark 16, the prototype Mark 28 and the production variant Mark 32. Marks 17-27 and 29-31 and this /60 calibre gun would be a post Mark 32 so even more missing numbers.

Info and history on the USN's gun development program from the cold war period seems quite sketchy with limited number of online sources and books to look for.
 
The 8"/55 Mk71 Major Caliber Lightweight Gun used a spare Des Moines class gun barrel in tests on USS Hull DD-945.


Your own reference says that the 8"/60 was "lengthened to improve range compared to the earlier 8"/55," and the only 8"/55 the US had in use was that Mk71.

This report has some of the history of the evolution of the Mk 71 here. Notably, it was originally built as a 175mm gun but rebored to 8-inch when the Army abandoned 175mm. It was definitely not a Mk 16 barrel, but they did compare wear to that of a Mk 16 (see pg 32; which is 44 in the PDF).

INTRODUCTION

The Major Caliber Lightweight Gun Mount (MCLGM) is a result of Navy and Marine Corps efforts beginning in 1960 to provide the fleet with the first major caliber gun mount to be designed since the end of World War II. This mount would provide firepower necessary to support troops ashore at ranges well beyond that of 5"0 guns and would provide greatly increased firepower for the fleet, particularly for smaller ships. A 175mm/60 caliber mount was specified by Reference 1 because of the potential advantages of achieving commonality in ammunition with the Army 175mm gun. Northern Ordnance Division of FMC Corporation at Minneapolis (NOD/fmc) was awarded the contract to design and develop the mount. A prototype was fabricated and subjected to testing at NOD/fmc, including a 50,000 cycle life and reliability test, on the loading system. The mount was disassembled and delivered to the Naval Weapons Laboratory, Dahlgren. Virginia in August 1970 where it was reassemble checked, proof-fired and evaluated to verify that contract requirements were met.

The Army, however, developed only one type of projectile for an anticipated family of ammunition; terminated plans for future ammunition development; planned the phaseout o! the 175mm gun; and commenced development of an "up-gunned" 8-inch howitzer. Accordingly, the original SOR, Reference 1, was revised and superseded by Reference 2 in October 1969. The MCLGM was directed to be an 8-inch gun in production using the basic design established in the development of the 175mm prototype To meet these new requirements, a program was authorized in February 1971 to convert the prototype MCLGM from its 175mm/60 configuration to an 8"/:55 Thus, the Naval Weapons Laboratory, by Reference 3, was assigned the responsibility to effect this conversion and to evaluate the 8"/55 MCLGM MARK 71 MOD 0.

The oscillating assembly was returned to NOD/fmc in March 1971 for modification of the recoil and counterrecoil system to handle the increased loads when firing 8".0 MARK 25 projectiles. Since the cartridge case remained the same for both the 175mm and 8*0 applications, only minor modifications were required to the ammunition handling system to accommodate the heavier projectile. These were accomplished on the mount without removing it from its permanent emplacement. Two 175mm liners were converted to an 8".0 by Watervhct Arsenal. A four caliber extension was added to one liner so that it might be used in the mount, the second liner was converted to an 8"/51 caliber test gun for interior ballistic development programs. Two new 8*/55 caliber liners were also machined from new forgings. The converted oscillating assembly was returned to NWL in August 1971 and the mount was reassembled. The 8".0 MCLGM prototype mount was proofed with the EX 28 MOD 0 liner (with the extension) on 3 September 1971.

 
Wow! Thanks! I think this provides the the missing marks between the Prototype and the production gun!
Mark 28 - the prototype 8"/55 gun converted from the first 175mm/60 gun
Mark 29 - a 175mm/60 gun relined to 8" but 4 calibre extension so 8"/59 gun?
Mark 30 - a 175mm/60 gun relined to 8"/51 test gun
Mark 31 - the two new 8"/55 guns manufactured from new forgings
Mark 32 - The final 8"/55 production variant
 
I disagree. Never heard that a spare 8"/55 RF Mark 16 barrel (if any survived by that time which seems unlikely knowing that the USS Newport News's gun did not replaced
They did have spare 8"55 barrels, literally multiple cruisers worth of them since the standard at tge tine was was 3 set of barrels per cruiser. With the Desmounes class get 4 sets due to the thought that their high rate of fife would burn out the barrels faster then they could be rebore, so they made spares.

What Newport News needed was an ENTIRETY NEW TURRET.

Cause that gun explosive completely and utterly FUCKED that turret. It was basically the Iowa Turret 2 explosion but worse. Since all tge powder cases in the hoists for the gun went up as well. It basically destroyed the center gun entire support structure. Think the breech, the rams for both elevation and loading, all the wiring, the shell and powder hoists, then entire deal was FUBARED.
 
Wow! Thanks! I think this provides the the missing marks between the Prototype and the production gun!
Mark 28 - the prototype 8"/55 gun converted from the first 175mm/60 gun
Mark 29 - a 175mm/60 gun relined to 8" but 4 calibre extension so 8"/59 gun?
Mark 30 - a 175mm/60 gun relined to 8"/51 test gun
Mark 31 - the two new 8"/55 guns manufactured from new forgings
Mark 32 - The final 8"/55 production variant

I don't think this tracks.

The first gun was a 175mm/60, which seems from the report to have used a totally new tube. There were (at least) two liners for this gun. When they rebored them to 203mm, one was left the original length, which amounted to an 8"/51. This had no EX number because it was strictly a test rig, not a working gun. The other was extended by 4 calibers, becoming an 8"/55, which I think is EX 28 MOD 0. Then there were two new 8"/55 tubes bored from scratch, which I believe were EX 28 Mod 1. The article refers to swapping EX 28 Mod 0 and EX 28 Mod 1 out for regunning tests. But then there's also an EX 30 gun, which appears out of nowhere and is never described. That was also swapping into the mount in place of the EX 28 at one point. This is not the 8"/51 test rig, because it's implied that the 51-caliber gun could not be mounted in the turret.

I think quite possibly they were only using even numbers for guns at this point.
 

Similar threads

Please donate to support the forum.

Back
Top Bottom