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Rab

Full length darts and high fps ?

Is there a maximum fps you can still use full length darts?

I'm thinking of pimping up the longshot again at some point,
I know theres benefits to using short darts but whats going to happen if you used standard ammo?

Cheers
OldNoob

The longshot creates several issues-
1- If you are not using a functional barrel (brass or similar) and sealed breech, the larger plunger volume creates problems with muzzle blast over about 100fps. I can't hit a barn door with my 120fps Longshot, but as people at tech day can attest my Retal, which has a sealed breech and functional short barrel appropriate to its smaller plunger volume is much more precise.
2- Dart mass distribution is what you tune for FPS. If the Centre of Mass is well forward vs the Centre if Pressure, then the darts flight will be stable. This is why elites spiral at over 90fps, their CM is starting to be behind the CP, making them "gimbal" in flight.
Stefans work because they have a shorter tail, which is both less affected by barrel blast and which puts the CM further forward.
3- Volumetrically the LS is very inefficient at lower spring rates, its big, slow plunger needs lots of spring to achieve the same velocity and volumetric efficiency as an elite plunger like the retal. A 10kg retal will shoot easily as hard, if not a little harder, than an equivalent LS. See my post in Chrono forum on ls vs retal.
4- Dart gate behaviour, the LS uses the dart tooth, with no gate. This can make it very picky with loading full length darts. If you have the stock bolt and breech, only certain darts are reliable. I found X tip foam too narrow and soft to be reliable and stacked worked better despite the lower mass. Some shoot koosh, not all. Most don't push the dart fully back into the bolt, wasting more power and increasing instability by reducing the effective barrel length.

If you want a decent LS then you can use full length darts, but only with a correctly tuned functional barrel and heavier darts.
Rab

Hmm, I've actually got my 14kg Longshot working really well.

I'd just had my head turned by the nerfturf 26kg combo spring and availability of metal parts.

Maybe I'll just park that idea and do a pump retal at some point, tbh I probably wouldn't have had a chance to use it anyway.

Cheers.
OldNoob

Most of those metal parts are entirely unnecessary as is the comically large spring. If you properly sleeperbreech the 14kg you have it will hit the top end of UK games anyway. Maybe you Irn Bru drinking types are more brawny than us wimpy southerners but 26kg, priming that is not going to be good for the joints.
The parts worth having on the LS are lipless breech (see PWND) Roboman bolt carrier, Roboman carbon priming rod, sleeper breech if you don't go lipless and some of the printed infill pieces they make to support things like the back of the plunger tube and back of the catch plate which bow under load due to the thin, open nature of the clamshell design.
Most of the metal parts are wholly pointless and adding mass to the plunger head is really dumb as it robs velocity. Also all the "pusher" type breeches using O rings are both unreliable and create unnecessary deadspace vs  brass ones where the dart fits INTO the bolt as in the stock system.

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