Use the same bullet - but change the plastic sabot. Below is a link to MMP sabots. You need the green ones (.429/.430). Retrieve the phone number thereto order. Ask them on the phone if they still make the HPH-24s in green 44/50s. I think they do. That's the thinner of the two offerings in green. These will replace the ones on your XTPs.

http://www.mmpsabots.com/green.html

Here's a better coefficient bullet for a terrific price. Try them with the supplied plastic sabot in the Omega. If they load too tightly, switch to the Black Harvesters.

http://www.midsouthshooterssupply.com/item.asp?sku=000308236

You pick out the place where you want to buy the black Harvester 45/50 sabots for the T/C Shockwaves. They will load the Shockwave bullet easier than the supplied sabot.

http://www.google.com/search?hl=en&q=HARVESTER+SABOTS&btnG=Googl e+Search

You can also purchase the Dead Centers & QTs/Extended Ranges online at a few places.

http://www.prbullet.com

http://www.cabelas.com

http://www.bpbullets.com