i had an idea for a cartridge to fill the role of 556 while offering many improvements

the main benefit of the cartridge is that you can carry nearly twice the ammo of 556.  the round is similar in size to a .45, so you can hold 4 magazines in a pouch, instead of 2.

overall mass/size is identical to a .45.

the round is case telescoped, with the bullet buried right to the bottom of the case.  a 'puller' sabot grips around the nose of the bullet, and then discards into 2 pieces downrange.

its just like the sabot on  a APFSDS round, exept we are shooting bullets, not darts. The sabot only grips the top 10mm of the bullet

the round uses compressed propellants.  expected muzzle energy is 1600ft lbs from a 23 inch barrel.

my question is do you think a 'puller' sabot would work.....the bullets are 30mm long so obiously a 'cup' sabot is impractical for such a small round

So two immediate comments.

1. Foot pounds of energy is an extremely poor metric for evaluating performance on paper.

2. Why are you giving the fpe expectation from a 23 inch barrel? You're not going to get anyone to accept a 23 inch barrel for basically anything these days!

There's just very little to comment on because you haven't given us enough much less the right information to give you any feedback.

What's the muzzle velocity?

Now what's the muzzle velocity from a reasonable barrel length? (Aka WAY LESS THAN A 23 INCH BARREL!)

What caliber is the actual projectile?

What's the BC SD etc?

What do you intend to DO with this round?

What kind of weapon do you want to use this round for?

I could list a couple dozen more questions but you get the drift.

So if you want to try again and give us more information I'd be happy to try to help you game this out