Minimum Indirect range of 25 Pounder and equivalents

Discussion in 'Gunners' started by instinct, Apr 17, 2011.

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  1. Hello Experts.

    What was the "minimum" range a 25 pounder could be used as a howitzer?

    Also if you know the same for other howitzers like the M101 or 10.5 cm leFH 18/40.

  2. G o o g l e
  3. My googling skills are crap but i did try.
  4. read about the Battle of Mirbat for a 25 pounder at close range
  5. With a maximum elevation of 45 degrees, could a 25 pdr be used for indirect fire?
  6. That's what a Howitzer is......

    That 25pdr wasn't being used in the Howitzer role at Mirbat.
  7. As the 25pdr could only be normally elevated to+45degrees it's max range was 13,400yds, if the tail was dug in it could maybe make+ 70degrees that would give a range of approx 8500-9000 yrds in the indirect (howitzer) roll , also dependent on charge used.

    The LeFH18 could only make +40 degrees and a range of 11,600 yds and the LeFH18(M) with upgraded ammo could make 13,400

    the term howitzer really just means that the gun did not need line of sight to the target and it was only when the 105 OTO Melara came into service could you shorten range by elevating over +45degreesas it could get +65 in normal situations
  8. Try this web site:
    25-pr data sheet

    The maximum range with the smallest charge was 3,900 yds. With the standard carriage on level ground one would have to reduce the elevation to reduce range, the exact point at which you think it stops being “used as a howitzer” is up to you.

    Dig the trail in and/or use the Mk 3 carriage and you can reduce range by increasing elevation, in theory you could dig the trail in so far that the shell goes straight up and then falls back on to the gun, so a range of zero. In practice there is a limit caused by the requirement for the shell to turn over at the top of the trajectory; fire at too high an angle and the shell will come down base first and the fuse will not function. I have no information on the angle this occurs at with the 25 pdr, however, 70 deg is the maximum the sights could cope with.
  9. Indirect fire means you lay using a gun aiming point, in contrast to direct fire where you use a direct fire telescope or even open sight to aim directly at the target. You can use indirect fire at any range you want, although I don't recommend it if you can see the whites of their eyes.

    25-pr was never designed to fire in the 'upper register' or 'high angle' as it's now known. In the final years of WW2 a bodge was introduced by having a dial sight adapter to keep the DS vertical, and bodge tables produced for false ranges that could be set on the sights. You also, as others have pointed out, had to either dig a spade hole or a wheel mound. Of course the Mk 3 carriage with trail cranking eliminated some need for earth moving. All this enabled upper register fire.

    Historically a howitzer did not have to have an elevation greater than 45 degrees, virtually none of the WW1 Brit field or heavy howitzers did. They achieved 'plunging fire', which is what howitzers were for, by having a choice of charges enabling a reasonably steep angle of descent at most ranges.
  10. Why do you want to know?

    Are you a wargamer trying to settle an argument or a historian trying to understand a historic event?

    You have the technical answer. There is no minimum indirect fire range, as "indirect fire" is a sighting method not a feature of the equipment. This may not help you solve the practical problem of whether a 25 pdr could hit a target behind a particular obstacle (building, woods or a ridge.

    From a practical point of view, if a target was behind cover and in range, mortars would be used rather than howitzers. The problem of crest clearance wasn't just about a minimum range, but configurations of ground at some distance from the guns. The problem was first noted in WW2 in Greece and Eritrea, but possibly had the greatest influence on the battle of Monte Cassino. The precipitous crests on the Monte Cassino massif and the altitude difference between the guns and the targets had the effect of neutralising the massive allied artillery advantage.

    Rather than worrying about the "minimum indirect range, the main development was to increase the range at which a target could be engaged with a higher trajectory. So in Burma and Borneo British and Australians artillery units might be equipped with 3" and then 4.2" Mortars to hit targets which could not be engaged by field guns or howitzers.
  11. With a bit of imagination and rudimentory engineering I'm pretty sure it could hit itself.
  12. Sympathetic_Reaction

    Sympathetic_Reaction LE Book Reviewer

    Theoretically with the correct orientation with respect to the spin of the earth, QE and flight time you could probably get it to land behind you....whether it would land fuse down or up might be a bit more complicated.

  13. An interesting piece of military trivia is that Minenwerfers had an all-ways fuse so that it did not matter if the projectile did not turn over. Most other rifled mortars/howitzers have a minimum range, below which the projectile will not land fuse first and hence not explode. Most mortars are fin stabilised which guarantees that the projectile will land fuse first.