Factors at play

December 3 2017 at 12:15 PM
Jason  (Login nervoustrigger)
YF12


Response to Re: Review of the Redesigned .177 JSB Monster pellet

True but at the same time, consensus is these factors tend to be less important with pellets. Probably the clearest practical example is twist rate. A flare stabilized projectile (diabolo pellet) doesn’t need much spin to fly straight. The extremely slow rate of twist delivered by a Smooth Twist is a good example.

The pros say the chamber / leade is less critical dimensionally and geometrically.

The role of velocity is less clear. Some have experimented with running the longer pellets like the Monsters over a wide range of velocities without a clear pattern emerging. If memory serves, the most compelling report I’ve seen was regarding a Thomas shooting them around 800fps in a much slower twist, and doing so well enough to win a competition. That runs counter to rimfire logic where the longer projectile benefits from a faster twist rate.

Lastly, even sizing is less critical. The skirt obturates to form a seal and as long as the head rides the rails, to borrow yrrah’s phrase, it seems the resulting accuracy is often quite good. He put up a nice experiment where he downsized pellets quite a lot before accuracy diminished. Again from memory, I think it was below 4.47mm which by most would be considered unacceptably undersized. Surely not all barrels would be as tolerant to the same degree but it does call into question the conventional wisdom regarding head sizes.

With that said, put all those in a blender with some barrel harmonics and a dash of wind and who can tell what’s important? happy.gif




 
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