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My 25 Cal Slug Rifle.. So Fare

August 4 2012 at 9:48 PM
Sean in VA-VB  (Login workinmanVA)
from IP address 98.183.197.222

25 Caliber Disco Slug Rifle

25 inch barrel:
.243 Bore .250 Groove 1:14 6 lands
Exhaust port .205 Dia

Modified valve:
.250 throat dia
.205 TP
Delrin valve stem w/ .315 OD
Valve stream lined to .110 and shorten to 1.010 from face to end of stem
Upgraded vale retaining screws to 10-32. Also added another 10-32 to front half of valve and added 8-32 to back half of valve for a total of 5 valve retaining screws.
Modified gauge port adapter

Rear cocking hammer assembly:
Total of 110 grams hammer weight
.300 Dia x .040 spring (.100 between each coil)

Standard Disco Trigger Group
Two screw mod

Breech modifications:
Bored bolt passage to .265 Dia
Extended bolt handle groove
Three set screws to retain barrel
Custom bolt and bolt handle

Specs with lighter hammer weight: (First Testing)
#1 810.9
#2 811.2
#3 805.7
#4 795.9
Fill PSI 2700 End PSI:1500
50 grn soft cast bullet sized to .249-.2495

* These #s were the first test #S Before upping the fill pressure and adding more hammer weight

Quick Spec. after adding hammer weight and upping fill pressure to 3000 PSI

50 grn soft cast sized to .2495 865 FPS

74 grn soft cast sized to .2495 692 FPS

74 grn soft cast sized to .251 632 FPS

A few pictures:

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Here are some targets I shot on my second day of test shooting. There was a pretty stiff cross wind this day. The first day of shooting I seemed to have a lot better grouping. So I hoping thats why my groups opened up, but Im out of bullet and Ill have to wait until I get more. I going up grade the trigger group to the Mrod trigger and play with sizing a bit. Try .251 and .250

50 YARDS
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Thanks for lookin
Sean Stephens
workinmanVA

 
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