60mm mortar

Discussion in 'Firearms' started by oil pan 4, Mar 16, 2022.


  1. oil pan 4

    oil pan 4 Monkey+++

    S is going to hit the fan.
    I have the 40mm grenade launcher, so not my first DD. Plus they say you can't fight an organized military with an AR15..... K.
    I bet Ukraine wouldn't turn down a shipping contain full of AR15s, or mosins, or glocks?


    It's a 3lb care package that leaves the muzzle at about 518fps, that 1,260ft.lb. of KE.
     
    Last edited: Mar 18, 2022
  2. Altoidfishfins

    Altoidfishfins Monkey+++ Site Supporter+

    Need the real ones.
     
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  3. duane

    duane Monkey+++

    Mortars and air strikes always scared the heck out of me. The tube artillery was accurate enough that if dug in away from some major target, you were fairly safe. A mortar is like an IED, just as likely to drop in your hole as not, left up to the fates and not your skill. Small man portable mortars for indirect fire and small anti aircraft and anti armor devices have always been game changers as was the IED. They force the other side to expend major resources for small threats. Thus every compound has to have thick blast walls, heavy overhead protection, and defense in depth. In several recent "police actions" the cost in lives and in money has been more than we have been willing to accept. While the movies are obsessed with the RPG, in real life a mortar or unguided rocket is just as big a threat and requires overhead as well as vertical protection.

    Germans in some ways were victims of their own success. Their enemies learned that their greatest weakness was the supply lines and given their lack of fuel, the railroads., and the bridges were the biggest liability in the rail system. Thus each bridge had to be guarded. It took several men to cover 1 guard position 24 hours a day and it took men on both sides and under the bridges to stop their destruction. Then the enemy could bring several men into the attack at one time and thus the Germans had to have a backup force close to the bridge. In USSR at the time of Stalingrad, some say that the Germans had about as many men guarding the supply routes as fighting on the front lines. Then as today, with snipers, RPG's, and mortars, no place is really ever safe. 60 mm is about the upper limit to being both man portable and easily moved and still having a major damage capability.

    Thanks for sharing your pictures of your "toys". The Karen's a hundred miles away must be in a panic.[peep]
     
  4. Dont

    Dont Just another old gray Jarhead Monkey

    Just need a little lathe work to make them effective.
     
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  5. sec_monkey

    sec_monkey SM Security Administrator

    da 60mm is too small

    git da 120mm [winkthumb]
     
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  6. oil pan 4

    oil pan 4 Monkey+++

    Those aren't mine.
    I was thinking something to span the gap between the M203 and it's 40x42mm shell which fires a 8oz projectile at 250fps. A 60mm mortar is 3lb at 518fps.
    And needs to be portable, 81 and 120 are way too big. I might buy some Trump mortars if I see them. I have very sandy soil so they should last a while.
     
    Last edited: Mar 17, 2022
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  7. oil pan 4

    oil pan 4 Monkey+++

    Does anyone know if a 60mm mortar is literally 60mm? I believe it is. Or what the bore diameter tends to be?
    The blueprints I found put the bore diameter at 60.45mm or 2.38 inches if you self identify as an imperialist.
    That sounds right if the projectiles are 60mm on the money.
     
  8. sec_monkey

    sec_monkey SM Security Administrator



    "I know nothing. I see nothing" .. ..
     
  9. oil pan 4

    oil pan 4 Monkey+++

    Oh it will all be legal. To quote a great senator "I will make it legal".
    The tube, free and clear to legally to make, buy, sell and trade (at least domestically)
    Base plate, free and clear to make buy sell and trade.
    The receiver, or the breach plug is the controlled part. It becomes a DD when it can fire fixed ammunition and could be joined with the tube, has threads cut into it or is welded to the tube. I don't want a welded one, it's just crude unrefined, generally non-repairable without a machine shop.

    Found some very pointy head technical international ballistic stuff.
    60mm M225 Fatigue Test and Burst Test
    The bore wear limit was 61.24mm, but found is safe at 61.5mm. Taking 25,000 to 26,000psi to burst even after being over bored and beaten like a rental mule.

    Thread diameter and thread pitch on the tube.
    2.837 to 2.835''×12tpi.
    2.783'' pitch diameter.
    With a 1.75'' long threaded portion.
    Tube diameter so a M5 bipod will clamp on.
    From 2.72'' to as much as .743"-2.747".

    Stoopid ebay
    USGI Reproduction 60mm Threaded Mortar Cup Machined from Solid Block | eBay
    (I deleted all the Google tracking jibberish)
    You can't buy an 80% lower but you can buy a 90% 60mm. You could drill a touch hole and screw on a tube, make a 60mm black powder mortar and that would be perfectly legal. Crude, but effective.
    Can't fire fixed ammunition with out a firing pin, so not a DD.
     
    Last edited: Mar 20, 2022
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  10. oil pan 4

    oil pan 4 Monkey+++

    I found a tube.
    3 inch outside diameter, 3/8'' wall 2.25 inch inside diameter 1020 steel DOM tube on metalsdepo dot com for $300 for 2 feet of tube. 4' for $500.
     
    Last edited: Mar 24, 2022
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  11. oil pan 4

    oil pan 4 Monkey+++

    My machinist can definitely turn down the outside of the tube, cut the threads on the tube. But he definitely can't bore the inside. Pretty much need a specialized line boring rig.
    I wonder how much a barrel even costs. Needing a specialized line boring machine may be why you almost never see new 60mm barrels. Too nitche, maybe?
    Nothing a little 18th century technology can't solve.
     
    Last edited: Mar 24, 2022
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  12. chelloveck

    chelloveck Diabolus Causidicus

    An interesting project, though I have to wonder about its practicality, given the use of TRUMP ammunition.

    As a former mortarman, and (medium mortar) platoon commander, back in the day, I am doubtful that the TRUMP 60mm mortar projectiles will be any more lethal than rather heavy (1.4 kg approx) yard darts, given that the blast and fragmentation properties of HE munitions is what causes much of the damage and casualty production downrange (WP adds incendiary effect to the blast and fragmentation effects). Unless one receives a direct hit, from a TRUMP round not much damage is likely, apart perhaps from one crapping one's tighty whities due to the psychological trauma of hearing the incoming and being in the impact area.

    I have fired the Brit 3" mortar
    [​IMG]
    (this videoclip would be very useful for getting insomniacs asleep :sleep:)

    The US M29 81mm Mortar
    [​IMG]
    M29, 81mm Mortar

    British L16 ('K' Mortar) (US M252 Mortar)
    [​IMG]
    L16 81mm mortar - Wikipedia

    Ordnance ML 4.2" Mortar
    [​IMG]
    ML 4.2-inch mortar - Wikipedia
    I commanded only 1 x 4.2" mortar team in support of an Arty mortar locating battery range practice..it was an interesting experience..the 4.2" bombs were very similar in design to the 3" rounds (just larger) using the same impact fuses and style of propellant charges (but larger).

    I don't want to discourage you from your project, but unless the rounds have a blast/fragmentation capability, then there seems little point to it, other than for its novelty value.

    For some more info on interesting info on the US 60mm mortar:

     
    Last edited: Mar 25, 2022
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  13. chelloveck

    chelloveck Diabolus Causidicus

    120mm is just a little heavy and cumbersome for insurgents to manpack. 80mm is doable with a lot of grunting and sweating. 60mm is a good calibre for platoon / company level organic fire support. More 60mm rounds can be man-packed than 81mm ammo which is a logistical issue for infantry at platoon/company level.

    There is a useful place on the battlefield for 60mm light mortar which can fill the gap between M203 40mm grenade launcher projectile and 81mm mortar supporting fire IMHO.
     
    Last edited: Mar 25, 2022
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  14. oil pan 4

    oil pan 4 Monkey+++

    It's same as using the 40mm M781 round in the M203 grenade launcher. It shoots and flies like the real thing. The M781 flies much further and at a flatter trajectory than I ever would have guessed.
    The trump mortars are just reusable projectiles that fly like the real thing. I would probably load them with orange marine signal smoke, to make them easier to find and reuse. The trump mortars are definitely not weapons.
    Assuming teotwawki and the "real ones" could become available.
    Actually in Afghanistan I found "presumed unexploded ordance" to be much more disruptive than a live round that went off. You find a something that looks like a mortar sitting in the middle of the road, now no one can go within 100 feet or so of that area and that road is closed till it gets taken care of which usually means all day. If the mortar went off, just drive around the crater. Were they duds or were they inert training rounds repainted to look live and shot at us? I don't know I wasn't EOD.
    If some one finds unexploded pieces of a rocket now it's an Easter egg hunt, trying to find the warhead or at least the fuse section.
     
    Last edited: Aug 21, 2022
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  15. oil pan 4

    oil pan 4 Monkey+++

    Yes, that's what I was thinking.
    Since RPG7 parts, such as separation and booster sections appear to be unobtainable here. A live RPG7 launcher, not that hard to get/make here.
     
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  16. duane

    duane Monkey+++

    As always in an civil situation, a device does not have to be effective, only appear to be. A 60 MM mortar round dropping anywhere near an occupying force or the use of a RPG requires both extended area monitoring and hardening of the facilities. Thus one ineffective mortar round would cause a major expenditure in all of the locations it may be used against. The same with IED's, as mentioned above, the threat will slow things down more than the actual explosion.

    Had a Spanish Mauser at one time, sights were set to be usable to about 2000 meters and were said to be some what effective to 1000 meters. I asked a Spanish Sargent about it one time, his answer was while at 1000 meters the target was the size of a tent, it might have some effect on a person sleeping in the tent if at random intervals holes appeared.:) Their thoughts were based on lessons learned in a long and bloody civil war.

    Some weapons, sniper rifles, 60 MM mortar, RPG, IED, resource denial, etc, favor the insurgents as they can both be hidden and have a standoff effect. In addition the recent experience has been that the more intensive your attempts to locate and destroy those weapons, the more you alienate the population and the harder it becomes to reach your desired goals. Even a simple step up to an 80 MM creates many problems in both hiding it and transporting it as well as the weight of the required ammo and a means of controlling its fire at a greater range. Modern tactics in insurgencies use weapons that are kind of like the effect of the old mule pack guns, not real effective in flat lands, but they were a game changer in mountain areas,

    Our experiences in the recent non major player wars has been bad, lost them all or declared victory and left.
     
    Last edited: Mar 25, 2022
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  17. oil pan 4

    oil pan 4 Monkey+++

    Toob.
    20221127_132742-1.
    Got it for $100 from a retirement auction.
    The internal bore diameter is 2.25'' an 5 feet long.
    So I can make 2 tubes from it and have a 1 foot log piece to fick up.
     
  18. sec_monkey

    sec_monkey SM Security Administrator


    :shock::shock:

    .. .. ya gots corrosion dere on dat toob .. ..

    .. .. looks like surface corrosion .. .. .. .. bttr git a close inspection done ta make sure da toob is safe ta use .. ..

    jus sayn
     
  19. oil pan 4

    oil pan 4 Monkey+++

    It was stored inside, I left it out in the winter storm.
     
  20. Tempstar

    Tempstar Monkey+++

    Machine shop time took me out of the mortar business, it was taking me 2 hours of lathe time per round. I have a 4" heavy wall tube now with an idea for a black powder cannon. I bought a complete 60mm mortar at a gun show in '85, (minus receiver and base) for $300. Sold it 20 years later for $1000 having never done anything with it. It was a good inspiration for a 2" version that used black powder and hand made shells. And yeah, I can just imagine how much the ol' sphincter tightens hearing one of those things dropping in with no idea how close it may come. Good psych weapon even without explosive shells.
     
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