PDA

View Full Version : figure this one out for me.



Lloyd Smale
11-03-2009, 08:54 AM
just got a new thompson omega inline 50 cal. Gave my old cva to the nehpew althogh for a few hours i considered trying to get it back from him. Took the new gun to the range. I always shot cast bullets in sabots in the old gun and had no problem getting 1.5 inch at a 100 yards out of it. Well i took a can of goex pinicle and some 44 and 45 cal bullets between 250 and 350 grain and the both sized sabots. I couldnt keep 3 shots on the paper at a 100 yards! I tried both calibers of bullets and nothing seemed to do it. When i got the goex i was clumpy in the can and i had to break it up so i brought it back and picked up a can of 777 that helped but i was still shooting about an 8 inch group at a 100 yards. Next i figured maybe it was the scope. i had put a old redfield 2x7 that had worked in the past but i wasnt confident in it so i went and bought a new scope for it. Same results. Well i was about to pack the gun up and bring it back figureing the something was drasticaly wrong with it. I got to looking in the box and it came with 6 ballistic tipped jacketed bullets and sabots. So i figured what the heck id try that. With 100 grains of 777 then shot into two in. Wow i was getting somewhere. I figured id go buy some more and be done with it but my cheap side won out. I knew i had a box of 250 xtps on the shelf at home and never had a use for them. I ran home and got them and they did 1.5 inch with 100 grains of powder and 1 inch with 90. Now tell me why this is. I shot 3 differnt 250-255 grain 45 cast bullet sized to 452 in the gun and couldnt keep it on the paper and 250 jacketed shoot into an inch. For the life of me i cant see why!!! I figured first it was the twist as it shot heavier bullets worse but both of these bullets should stabilize at about the same twist rate.

SPRINGFIELDM141972
11-03-2009, 09:54 AM
Just a couple of thoughts...

Were the lead boolits in the sabots lubed? If so maybe the lube was affecting the sabots ride down the bore.

How are the boolits seating in the sabots? I know you stated that you had used the lead boolit/sabot combination in another gun, but if the base of the boolit doesn't fit into the base of the sabot correctly it maybe cause issues with this gun. I would suggest you try a bevel base boolit in your sabots and compare.

Regards,
Everett

Underclocked
11-03-2009, 01:25 PM
SPRINGFIELDM141972, I think you have probably nailed the cause. My specific guess would have been the sabots not releasing evenly from the bullets either due to lube or even the lube grooves themselves. Did they load pretty tight? I would think the tighter the fit, the more pronounced that effect might be.

If I was going to shoot casts in a sabot, I would try them unlubed.

runnin lead
11-03-2009, 02:37 PM
It also might be worth trying to size them w/o lube to the same size as the jacketed bullets that worked.

mooman76
11-03-2009, 08:37 PM
I believe it may be bullet fit to sabot. I have never got into the sabot thing but you did say you tried two different caliber bullets and they need to be a good tight fit. If not the sabot could spin and not the bullet and the bullet won't stablize. Also think maybe these guys are onto somethnig with the lube.