What BB weight is best for TM M4 MWS stock?

[Chai.]

I am currently using 0.25 but they look to be going up when firing from a distance and not that consistent in grouping.

Do I need to go heavier? 

[Rogerborg]

50 minutes ago, Chai. said:

they look to be going up when firing from a distance

 

Er, then adjust the hop?

 

Generally you'll want to go as heavy as your hop can lift without losing significant muzzle energy.

 

For example, I can run 0.2g at 1.2J, or 0.28g at 1J, with the lower energy coming from having to exert more hop pressure.  I run the 0.28g though, as it ends up going further, more consistently, than lighter BBs.

 

If you can lift it, 0.3g or 0.32g is even better.  It costs more per magazine, but not necessarily per hit.

[Adolf Hamster]

1 hour ago, Chai. said:

they look to be going up when firing from a distance

 

that's god's way of telling you to use heavier ammo.

 

for the most part @Rogerborg is spot on, although it's worth noting his numbers might not be what you'd see.

 

as it's a gas gun, the assumption of more weight=more hop pressure=more bb resistance=less muzzle energy is being counteracted by the wonderful phenomenon of joule creep.

 

this means you might see your energy rise with heavier ammo, possibly enough to put you foul of the limits, so be sure to chrono in joules with the ammo you're intending to use and have the appropriate weight set on the chrono (or know the conversion/limit for your chosen weight/site limit)

 

21 minutes ago, Rogerborg said:

It costs more per magazine, but not necessarily per hit.

 

quoted for truth

[Impulse]

I generally like .32s, but the stock rubber won't lift them out of the box and you may see it creep over the limit on certain gasses, however there's a very simple and cheap upgrade part called the sixG nub. Honestly, the sixG nub is the only upgrade you really need to do with these for them to shoot pretty damn well on green gas all year round (height of winter at temps under 5 celcius you may need red gas)

[Rogerborg]

15 hours ago, Adolf Hamster said:

as it's a gas gun, the assumption of more weight=more hop pressure=more bb resistance=less muzzle energy is being counteracted by the wonderful phenomenon of joule creep

 

True, although I don't have to check my thermometer, barometer, and horoscope before packing my bag.  

[Argyld]

I think the heaviest for a stock MWS was 0.28, maybe 0.30

Heavier and you need a to change the hop-up rubber.

[Wavey_Gravey]

Mine always over hopped on 28’s, 0.30’s where the sweet spot, stock rubber / nub.

[Impulse]

3 hours ago, Rogerborg said:

 

True, although I don't have to check my thermometer, barometer, and horoscope before packing my bag.  

 

As someone who pretty much exclusively uses gas guns (gas snipers, worst of all!), it's a fun part of the hobby laying down a tarot reading, consulting the stars and making an offering to mother nature every night before a game day. Puts the ritual back in pre-game day rituals.

[RobHedley]

I run .32 in both of my MWS. Both have the SixG nub and Modify Tan Bucking and I have to dial off the hop as it send them skywards otherwise.

 

Never had a problem with running hot ever. In fact most manning the chrono look at me as if to say ‘that’s a bit low’. Then they see the BBs disappearing into the distance. Ah, the TM fairy magic!!