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Old May 9, 2021, 07:53 AM   #26
JohnKSa
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SO you have to understand the context when someone uses the term RPM.
Indeed. Fortunately the OP's context is quite clear--the question is obviously about cyclic rate.
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What controls the rate of fire on an automatic weapon, bullet weight, recoil spring tension???
It depends on the type of action, to begin with.

The cyclic rate of a gas-operated gun can be increased by allowing more gas into the action. That's assuming the action is designed to handle it.

In a recoil operated gun, lightening the recoiling mass will generally increase the cyclic rate, depending on how the locking mechanism is set up. And, again, assuming the action is designed to handle the extra energy of the recoiling mass.

I think asking about one specific gun might net some more useful responses. I think asking the general question opens things up so wide that it's hard to give a good answer.
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Old May 11, 2021, 01:47 PM   #27
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It depends on the type of action, to begin with.
Often it ends with the type of action, as well.

Sometimes, increasing the gas doesn't result in any appreciable change to the cycling rate it just makes the parts slam harder. Yes its because they are moving faster but the result is dependent on the specific action particulars.

Adjustable gas systems on some belt fed guns are there to provide more gas to keep the action running when it becomes sluggish due to the build up of heat, firing residue, loss of lube or foreign matter found in combat conditions.

Other "adustable" systems are not firing point adjustable, requiring changes in buffers and/ or springs or other parts to change the firing rate.

How much can be changed and how it is done is entirely dependent on the design of the action. There's no free lunch.
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Old May 27, 2021, 06:36 AM   #28
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In the very early 70's I was trained as a M-60 gunner to shoot 3-5 round bursts. We shot at 55 gal. drums 1100 meters distant. Every 5th round a tracer made it easy to walk your shots to where you needed them. I will add that while the M-60 was my assigned weapon I never fired it in anger and was happy about that.

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Old May 28, 2021, 06:57 AM   #29
Willie Lowman
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There have been a few open bolt submachineguns made where weight can be added or removed from the bolt to change the rate of fire.
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Old May 29, 2021, 11:24 PM   #30
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There have been a few open bolt submachineguns made where weight can be added or removed from the bolt to change the rate of fire.
Which ones would those be??

and, are you talking swapping a bolt for a heavier one, or using the regular set up and adding or removing weight somewhere?
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Old May 30, 2021, 11:48 AM   #31
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Originally Posted by PolarFBear View Post
Every gun has a rate of fire, battle ships 2 shots a minute; M-60, 900 rounds a minute. What controls the rate of fire on an automatic weapon, bullet weight, recoil spring tension???
900 rounds a minute? Usually, it's the machingunner's finger that controls the rate of fire.
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Old May 30, 2021, 02:59 PM   #32
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Which ones would those be??
The Czech ZK-383 and the Stemple take down gun come to mind. Both had weights you could add or remove from the bolt to change the rate of fire.

https://www.youtube.com/watch?v=MlFdhAK5c7Q
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Old June 4, 2021, 08:48 AM   #33
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The weight of bolt and the length of recoil stroke. The rate of fire is not affected by the trigger. Some MGs can up RPM by putting spacers in recoil buffer. As long as complete cycle can be made without metal to metal contact. There is a limit on the rounds per minute on any given conventional gun. There are many ways to slow them down.
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Old June 6, 2021, 11:18 PM   #34
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The rate of fire is not affected by the trigger.
The cyclic rate of the action is not affected by the trigger, (or the gunner's trigger finger). RPM (rounds per minute) is the term used for the cyclic rate.

The rate of fire, the actual amount of ammo that can be fired in one minute, is ALSO expressed as RPM, but is subject to the gunner's finger, and the amount of ammo that can be fed into the chamber.

So you have to be aware of the context to understand the differences.

A box magazine fed machine gun has an actual rate of fire much lower than the cyclic rate of the action. A belt fed can potentially run at the action's cyclic rate, IF you have enough belts linked together and can keep them feeding smoothly.

However, air cooled types are still subject to heat build up during continuous fire which at some point will render the weapon inoperable.
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