Old School D.I.S.C. Quick Release Bolt Conversion (PICS)

If you have ever had the pleasure of using the quick release (pull-pin) bolt release on any of the newer D.I.S.C. Rifles, and then have one of the older Allen head screw models you will know what I am talking about. I have an older .45 cal 1:20 twist D.I.S.C. barrel that had the allen head screw, I have been spoiled by the newer quick release on the newer Eltreme and Elite. If you are shooting the new NFPJ conversion shooting heavy loads, you will get an occasional stuck primer that swelled a little more than the rest. If you get a stubborn one that doesn't want to drop out, it is a pain to get and Allen wrench vs just a pull on the pin. This could really be a problem if you needed a follow up shot while hunting, and you didn't have an Allen wrench with you.

I ordered a couple of the "Quick Release Bolt Screw Assembly", Part # 008462 from Knight about 10 days ago. Next, I needed to find a #2 drill and a 1/4-36 tap, which a very nice gentleman offered me the use of, and some insight as to performing the operation. I just hope to be able to return the favor in the future. The drills and tap arrived in the mail, and I was able to make this conversion today.


This is what I started with, for those that are not familiar with these rifles. Notice the Allen head bolt that requires two full turns to back out far enough to remove the bolt.



Here is a shot of the hole and the tools to get the job done. Notice the Allen head bolt on the left and the new quick release pin on the right.



My el'cheapo drill press isn't the best, but it was a gift so I guess I can't complain. Next I needed to drill the hole to accept the 1/4-36 tap. I did this in a 2 step operation first using a #3 drill, then followed by a #2 drill to get the correct diameter hole for the tap. After drilling & tapping I cleaned up the oil and chips. There was a very small burr on the inside of the hole which I removed. You will need a 1/4" socket to install the new quick release.



Here is the final product, I'm happy to report it is a perfect fit.



And for the moment of truth, with the bolt installed. Very happy with the way it turned out.


I am not sure what Knight charges for this conversion/upgrade, but whatever it is, it would be worth it. I think RT just sent his in IIRC, he might be able to tell you. If you have been on the fence about sending one in to Knight, you might want to do it while it is still being offered. Hard telling how long they will be offering these services, or if they even will be offered after June 30th?

nice post with good pics, I sent knight an e-mail to see if they can add one to an order I sent in yesterday. Thanks for the info.
Doug

Why don't I see that part or part number when I do a search on the Knight web-site?
Doug

dalberg said:

Why don't I see that part or part number when I do a search on the Knight web-site?
Doug

Click to expand...

If you check page 25 in the Owners Manual (in link below), it is part "S14" on the schematic, then go to page 47 (top line) Item # 008462.

Part
Ref.
Model
No.
Description
S14 008462 SCREW, Quick Release Detent, DISC EXTREME, MHL DISC EXTREME

http://www.knightrifles.com/instructionmanual/default

thanks, I found it I will see what they tell me.
Doug

Busta: I sent 2 barreled actions to Knight for this installation about two weeks ago. They charged me $30 each. Not sure if that included return shipping because I ordered other stuff too.

Don't know if I would have attemped it myself. Looks like you get one shot at it.. and if you screw it up.... :shock:

So was the set up hard at all? Without looking(guns are all tucked away at the moment) I can't picture a flat surface to index from.

It would've been nice if the old allen head threads and the new quick release threads were the same size and you could just unscrew one, and put the other in, that would make too much sense though woudn't it?

If that were the case, the stop would be very loose in the bolt opening.

Critter said:

So was the set up hard at all? Without looking(guns are all tucked away at the moment) I can't picture a flat surface to index from.

Click to expand...

critter,

IF your scope base is TDC, which mine isn't. They are slightly to the right of TDC. You can use your scope base clamped in a vise to keep things square. You may have to shim just a bit to get things square. The scope bases were actually a good thing. The material actually came out pretty easy.

howa,

The spring loaded pull-pin in the quick release has to be a large enough diameter to hold up to the bolt movement. This was designed several years after the introduction of the Disc rifle, and the original bolt is solid, so it didn't need to be as big. If they had tried to make the new one the same size, the pin inside would have had to be such a small diameter and they would just shear off under use. There is a spring housed inside that assembly as well as the pin.

busta

Looks like you goter done, knew you would
Wayles

I'm about to drill out the hole for an upgrade on the quick release pin, I'm going to see if the recoil lug is square to the pin hole. If so a piece of leather on the barrel side of the clamp to protect the barrel and I should be good to go. :yeah:

Update on the QRBC, it's such an easy process with a drill press and a #3 drill then a #2 drill followed up with a 1/4x 36 tap. I did 4 in just over a half hour. :yeah:

I do have an extra NEW TAP 1/4x36 if anyone needs one. $19.95 plus shipping.

Sorry for digging up an old thread, but I would rather dig this up than create a new one.

I am probably over complicating this but, for anyone who has done this... did you use a standard Taper Chamfer or a plug chamfer tap? Just thinking that to get to full thread on a taper chamfer you have to screw the tap 8 to 10 threads out the other side. I don't want to run the tap into the other side of the action...

Just don't want to spend $ on a tap and find out I need a different one.

I just used this one from amazon. Be careful, go slow, use oil. With the bolt out there is plenty of room to go thru. I broke one trying to rush it. Dont do that.
https://www.amazon.com/dp/B00BQ2JX2C/ref=cm_sw_r_cp_apa_fab_qGGHFbCK714ER

Amazon for taps... Go figure. I can order taps/drill bits at work and usually it saves money as they get shipped with work stuff and I don't have to pay shipping. In this case amazon is $3 cheaper. I had never really thought about amazon for drill bits/taps ect. Thanks for the link.

For anyone's future reference. The linked Tap is a Plug Chamfer Tap.

I bought it from amazon, cuz i knew i would only use it once or twice, instead of buying from snapon for 10x the price.

I just did mine a few months ago. Pretty easy just take your time. I can send you my drill and tap. PM me if you want to use it.

Fwiw, i drilled both of mine by hand. No drill press or anything just my cordless drill. Just eyeballed it and went slow. The existing hole will keep your drill going straight. But i have been a mechanic for 34 years and do that kind of stuff a lot.

I used a drill press a jacked around with getting the barrel level and square. It took me longer to set up than it did to actually drill and tap. After I did it I think michiganmuzzy's way is just as good if not better.

I have both drill bits and the tap if anyone needs it let me know.