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What weight would be recommended for a G&G SR-25 because I don't want to buy 0.2 and there useless or 0.3 and are too heavy for the m100 spring

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If you really want to start using your SR-25 to it's full potential, open it's gearbox up/pay a tech to and start getting upgrade parts for it. An M120/M130 would be a good start, and you'll see immediate range benefits by using heavier BBs such as 0.30s, as they retain more kinetic energy through their flight than a 0.25g does.

Have a look at upgrade guides or ask around if you want to know how to get the best out of your SR-25, as without upgrades it's basically an inconveniently large assault rifle locked to semi :)

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If you really want to start using your SR-25 to it's full potential, open it's gearbox up/pay a tech to and start getting upgrade parts for it. An M120/M130 would be a good start, and you'll see immediate range benefits by using heavier BBs such as 0.30s, as they retain more kinetic energy through their flight than a 0.25g does.

Have a look at upgrade guides or ask around if you want to know how to get the best out of your SR-25, as without upgrades it's basically an inconveniently large assault rifle locked to semi :)

 

Probably not a good idea for him to start upping the FPS with the current BS that Salmond is trying to push through the Scottish Parliament.

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I've tried finding out in this forum, and by emailing pro airsoft supplies, but what would be the best pellets for the G&G combat machine cm16?

With some airsoft videos I've seen and stuff I've read up on I think some people use .23's and .25's in skirmishes.

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Or if you're running a support gun where a pot of ammo = 1 mag and lasts you a single game.

Then lighter ammo is a lot cheaper, and the volume of fire makes up for most of the disadvantages of having less accuracy and range... But it's mostly a cost issue lol

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0.25g makes a lot of accuracy difference for me in doors at just 10m when compared to 0.20g. 0.28g also makes even more difference. At some point the projectile gets too slow to be used effectively against moving targets, but the heavier BBs for me at least seem to be measurably more accurate.

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0.25g makes a lot of accuracy difference for me in doors at just 10m when compared to 0.20g. 0.28g also makes even more difference. At some point the projectile gets too slow to be used effectively against moving targets, but the heavier BBs for me at least seem to be measurably more accurate.

 

It's all in your head, the difference in time to target below 50' with a .20 and a .30 is very small fractions of a second:

 

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I have to say I'm pretty impressed by the data James is quoting above, but I believe that the performance of your hop set up is key to matching those results. In my experience you can have to put the hop on so much to lift heavy BB's that you do not get the benefits of extra range, because the power is reduced. The best bet then is to experiment.

 

But an SR-25 really should be putting out enough power that 0.25g is the minimum weight to use. Still, just because an AEG looks like a DMR doesn't mean it has the internals to perform as one. If you don't want to up the power to 1.6-ish Joules, a DMR should still be consistently very close to your fav site's limit. Consistency can be increased by a better air seal, which also increases the power without changing the spring, and increases accuracy, since the BBs' trajectory will be more similar.

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If you play at Spartan, they are Bio only and you will have to buy from them anyway.

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I have to say I'm pretty impressed by the data James is quoting above, but I believe that the performance of your hop set up is key to matching those results. In my experience you can have to put the hop on so much to lift heavy BB's that you do not get the benefits of extra range, because the power is reduced. The best bet then is to experiment.

 

But an SR-25 really should be putting out enough power that 0.25g is the minimum weight to use. Still, just because an AEG looks like a DMR doesn't mean it has the internals to perform as one. If you don't want to up the power to 1.6-ish Joules, a DMR should still be consistently very close to your fav site's limit. Consistency can be increased by a better air seal, which also increases the power without changing the spring, and increases accuracy, since the BBs' trajectory will be more similar.

 

Those numbers are based on hop-up settings to provide a straight and level trajectory for as far as possible. The amount of hop-up required is largely irrelevant as the maths is based on the muzzle energy rather than the energy output of the spring. A gun which only requires one click of hop-up to lift a .25g BB with a muzzle velocity of 350fps is functionally identical to a gun that requires 10 clicks of hop-up to lift a .25g bb with a muzzle velocity of 350fps.

 

Only time the amount of hop needed would be relevant is if the experiments/models were done based on a gun which was chronod with hop-up off, a rule which I think when implemented is completely retarded!

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the site i use is bio only too so i buy from them although they do offer both .20 or .30. i havent tried .30 but i am considering it for the G3 although i am not sure what kind of difference it will make at its current 270fps or after its upgraded to 330 fps

 

.20 will do for the pistols, especially the desert eagle (the only one with auto)

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the site i use is bio only too so i buy from them although they do offer both .20 or .30. i havent tried .30 but i am considering it for the G3 although i am not sure what kind of difference it will make at its current 270fps or after its upgraded to 330 fps

 

.20 will do for the pistols, especially the desert eagle (the only one with auto)

.3s will be way too heavy at that FPS, stick the .2s, or pick up something like 25s online.

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.25s are better.

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Those numbers are based on hop-up settings to provide a straight and level trajectory for as far as possible. The amount of hop-up required is largely irrelevant as the maths is based on the muzzle energy rather than the energy output of the spring. A gun which only requires one click of hop-up to lift a .25g BB with a muzzle velocity of 350fps is functionally identical to a gun that requires 10 clicks of hop-up to lift a .25g bb with a muzzle velocity of 350fps.

 

Only time the amount of hop needed would be relevant is if the experiments/models were done based on a gun which was chronod with hop-up off, a rule which I think when implemented is completely retarded!

I don't think you and I are talking about the same thing. Fair enough, if your intention is to scientifically compare shots with equal muzzle energy so that the only variable is the BB weight, so for eg at 1.14J a 0.2g BB has a muzzle velocity of 350FPS and a 0.25g BB has 313FPS - but these are figures derived from maths. To actually achieve these equal muzzle energies/velocities you could not simply load different ammo into the same gun and set the hop, because in the real world applying more hop to lift a heavier BB reduces the muzzle velocity more than simply the change in weight would suggest. I doubt many people have ever thought much about this because we expect to lose velocity when we use heavier BB's; what drew my attention to it was fitting a Falcon 455x6.03mm TBB with the Dual Point hop rubber...

 

It really struggles to lift .25's, so when I slide enough hop on (it's an AK: no clicks) to get the best range possible with flatish trajectory, the result is 5-6m less than I can get firing 0.2's... (is this the dreaded one gun phenomena conflated erroneously with fairies at the bottom of the garden, et al, a la Ed's comment above perhaps... read on and decide for yourselves).

 

...which made me think the whole process through again - I had thought about it a bit back when we were considering the alleged phenomena of 'Joule creep'. TBH I can't remember the complex reasoning of the discussion, although it is somewhere within these hallowed pages, but i do remember thinking that it didn't matter anyway because of the way in which hop up works - basically it is a brake designed to fail: if the brake succeeded the BB would be stopped completely (and some hop units can do this, much to the annoyance of a steady stream of noobs whom we meet here at their wit's end), but by only partially succeeding the braking effect is applied to one side of the BB resulting in backspin - but here is the point:

 

braking occurs

...and more hop on equals more braking. I just did a quick test on my chrono to illustrate the point: the average of 10 shots with no hop firing 0.2's was 353.45FPS vs 321.27 with hop set for max range flat traj. It's dark so I can't see to set the hop with 0.25's (it was left on set for 0.2's) But you all know this. So why is it difficult to swallow that applying more hop to lift heavier BB's reduces the energy those BB's carry as momentum, over and above the velocity lost by a heavier object given a similar impetus?

 

There are other complicating factors also, such as how whatever imperfections there are in the air seal from piston head to barrel will behave differently under the changing pressure over the time it takes for the BB to exit the barrel and since this is different for different weights of BB, it is undoubtedly a factor*, just one which would need a pretty complex set up to measure. But hey, that just means that you really do need to experiment with your guns to find what works for you, as has been said.

 

*Simply changing the piston head to a dual O-ring type gives approx +20FPS / Modify Hybrid barrel & hop rubber combo can give +30FPS over and above whatever may be gained by changing a stock 6.08mm barrel to a 6.03mm TBB, so airseal and changes in its performance are significant.

 

But a blanket statement that 0.25's are better is not helpful. I agree that people do believe things which the evidence observed by someone else seems to disprove and otherwise sensible people have apparently witnessed evidence for things which just simply cannot be true** - maybe some of you remember the fad known as 'suckback' where it was believed by some that if you did not have sufficient air volume in your cylinder (because of vents) to make certain that the air was still expanding the whole time that the BB was travelling down the barrel, then in long barrelled AEG's when the piston was pulled back ready for the next shot the BB would be retarded by air being sucked back down the barrel. Well, you only have to work out the time the BB spends in the barrel compared to the cycle speed of the gearbox to know that this is impossible, but besides that, there are vents in the piston head which allow air to fill the cylinder from behind the piston head - but people wrote on forums and told me f2f that they had tested it with a chrono etc. You know what, I'm willing to believe that people would hallucinate better results with .25's because they believe they must be better in all circumstances.

 

There are different hardnesses of hop rubber: generally speaking the softer / lower the degree, the stickier the rubber and the stickier it is the less 'hop on' you need to lift any BB, but also the softer the faster they wear out, so if you have a high FPS gun you can use a harder rubber because you have power to spare, but this is also desirable because higher power guns wear their hop rubbers out faster. But most stock rubbers are made to work ok and last a fair while - a couple of years of average use, say once or twice a month skirmishing all day and a bit of plinking in between, and also bear in mind that, with the exception of Japanese guns, almost all AEG's are designed to be at least 25% more powerful than UK limits.

 

So going back to the beginning of this post, do you think that it is only funky hop rubbers such as Falcon Dual Point which can result in losing more power by putting enough hop on to lift .25g BB's than is made up for by additional range gained by conservation of momentum vs air resistance in denser BBs, or do you think that some guns downgraded to M100 springs with stock rubbers may suffer the same effect, bearing in mind that the difference or perhaps similar but not as extreme, so that what they gain from more weight is lost to additional braking? Perhaps you think as I do, that due to our UK FPS limits, if 0.23's were more easily available and cheaper, they would probably be a better choice than 0.2's or 0.25's for many UK guns, but in the absence of an overnight miracle, you should suck it an see...

 

**I wonder if you were referring to our conversation Ed when I said that I was getting 70m accurate for man sized target shots from my tac AK? I know. It sounds impossible, but I swear, @MCG The Gaol firing out of the window of 1 cell block, across the path through the main gates into the yard of the main block with the refectory etc in it, the entire length of that block to targets standing around believing they could not be hit by people 15-20m closer to them than I - not flat trajectory, but not walked onto target lobs either, aimed shots at an upward angle - approx 346-7FPS (using a Magic Box double O-ring piston head, lashings of CT-2 grease, unbranded ali O-ring nozzle, lonex hop unit, G&G green rubber, PTFE tape wrapped hop rubber, Madbull fishbone spacer, 6.04mm TBB (i had to downgrade the spring to some poxy shotgun spring i got in a job lot of parts because i was getting over 380 with an M100) and Blaster .25g BB's ;) she died about 15mins from the end of the day grrrr - but she shall return weyhey!

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