and gear carrier retainer ring 600 triangular shaped gear carrier block 536 has a pinion shaft aperture 536a so that it may fit onto or over the one end 513a of charging handle pinion gear shaft 513 together with wave washer 571 backup washer 572 which also receives driver pinion gear 518a fiber washer 583 and pinion shaft bearing 520c as shown charge carrier gear block 536 has an idler pinion gear aperture 536s for receiving idler pinion gear 518s using idler gear bearing 570 idler gear roller 569 and idler gear shaft 568 a gear carrier stop 557 having a larger diameter stop end 557a and a smaller diameter end 557b uses larger diameter stop end 557a to stop movement of tapered or triangular end 536c of gear carrier 536 the larger end 537a fits through gear carrier stop aperture 512a of upper gear housing 512 and gear carrier stop aperture 510a so that larger diameter stop end 557b extends towards the interior of main internal housing 511 so as to interfere with movement of the pinion gear carrier 536 in this way it may stop or limit movement of the triangular end 536c of gear carrier 536 as shown in fig1 17 and 18 the pinion shaft 513 which is part of pinion gear assembly 630 which comprises pinion gear carrier 536 and pinion gears 518 fits into pinion shaft bearing 520a which fits into pinion shaft aperture 510b of lower gear housing 510 the pinion shaft 513 also fits into worm gear 507 and unidirectional clutch 519a both of which reside between the lower and upper gear housings 510 and 512 additionally pinion shaft 513 extends through pinion shaft aperture 512b.