[Clay]

Chief Dave, Ted, other RKI's: help with 77/22lr : 77/17 conversion!

The parts arrived from Ruger today and I started to assemble the rifle in the laminated 77/22mag stock. Everything drops right in with the exception of the bolt ............ the steel piece that holds the mag latch plunger for the 77/22 magnum is much different in dimension than the same part from the 77/22 long rifle out of the synthetic stock and appears to keep the bolt from traveling forward far enough to allow the bolt handle to close. Looks very close in regards to the position of the bolt handle and the cut out, but no dice. I haven't modified anything yet.

What do I do next?

Thanks,
Clay

 

[050]

Chief says : the synthetic stock has no parts that can be salvaged to work on the conversion.
the action complete should be able to assebbled and function
out of the stock.
heres a pic - which area is giving the problem?

 

[Clay]

"B

I think it is "B", the piece that mag latch plunger is mounted in. The bolt closes as it should when the standard .22lr piece is installed, but will not close - actually looks as if the bolt is closed, but the bolt handle will not move down to close (or turn) the bolt. I don't understand what could be holding it up.

 

[Clay]

Pic of new .22magnum complete trigger guard assembly

Here is the new 77/22mag complete trigger guard assembly in place. Bolt closes and locks down nicely with the old 77/22lr part in place. Will not allow the bolt to completely close and the bolt handle turn down to the resting position.

 

[Clay]

My Vision ..........

Well, at least the whole rig looks fantastic sitting in the cradle!!!

 

[calumet]

Clay, You may be suffering the same problems I encountered when converting my older vintage 1986 77/22lr to 17HMR.
If so, the problem lies in the ejector groove in the bottom of the front half of the bolt. It is not machined through, as in the newer models, & requires a little reshaping with a moto tool, or your local gunsmith. On older bolts, the ejector groove ends at the back of the front half, & the inside of the groove ( I think closest to the center) is rounded, the other side is straight. The rounded side must be squared up to match the other side, then your bolt should close. If you have access to two different bolts of early & late model rifles, you'll see the difference. Another solution may be to compare the thickness of the ejector abutment on the new trigger guard assy against the original & file as necessary on the back side to make equal thickness.
Good luck, You're almost there, & ya surely wont be dissapointed Best Calumet

 

[calumet]

Clay, to clarify ejector abutment, it is "B" in Chief Dave's photo
Good luck! Calumet

 

[050]

Chief says : calumet is ontop of this one.

that has to be the fix to the problem . though I never encountered it in my conversions . not much else would
stop the bolt from locking down. do compare the ejector heights.

Maybe Plinker or Ted can shed more light on this.

Chiefdave

 

[Clay]

Thanks, Calumet

You must be right. That would explain the bolt not traveling quite far enough and the inablility of the bolt handle/sleeve to turn down. I called Ruger and they won't sell the bolt sleeve or the breech block portion of the bolt either - I was looking for the 'quick fix' and it ain't there.

Do you have any pics of how your bolt bottom looks after you made the mods?

Or can someone please post a closeup pic of the bottom of a 77/22mag bolt?

Any dimensions that anyone has as to the length and width of the ejector groove and the other groove on the bottom of a 77/22mag bolt would also be greatly appreciated.

Not sure about making mods to the ejector abutment for the 77/22mag, although I'd rather modify the ejector abutment than the bolt. While making mods to the abutment might allow the bolt to travel forward to the closed position, I don't know if those mods will allow the bolt handle to turn down .................

Thinking about your mods where you describe the groove next to the ejector groove on the bottom of the bolt needing to be symetrical, instead of straight on one side and rounded on the other.

 

[TaleGunner]

BREECH BLOCK !!!

Clay, The part that is giving you the problem is the breech block (The front part of the bolt) I've looked up the part # in ruger parts manual & it listed different part # for mag. & L.R. rifles.
Rod

 

[Clay]

Thanks, TaleGunner ..........

Just took a closer look at everything and you guys are right. The ejector groove in the bottom of the breech block is not long enough to allow the bolt to travel completely forward into a closed position. Ruger won't sell the breech block part - she said it is a factory installed part *ONLY* and Ruger doesn't sell those as a part. I suppose you could send the entire rifle in witout a bolt assembly and ask them to replace it? But my receiver is marked "77/22" and I would probably get the .22lr part again.

Looks like I could modify the ejector groove ............. or maybe just machine the back curved portion of the ejector abutment that rides in the ejector groove??? Looks like this mod would allow the bolt to travel forward into the closed position and we wouldn't be modifying the breech block.

Based on measurements I just made, it appears that a little more than .050" but less than .060" movement is necessary and I believe this could be accomplished by carefully removing material from the back curved portion of the ejector abutment.

I like this option much better: screw up breech block = send rifle back to Ruger and beg for replacement at who know how many $$ and on their time schedule. Screw up mods on ejector abutment = order another 77/22mag complete trigger guard assembly from Ruger for $46.00.

What do you fellas think about it?

Thanks,
Clay

 

[Clay]

Ejector Groove Contour Pic

Don't want to make this mod unless it is the only way ~~^>).

 

[Clay]

And yet another pic ......

used drill bits to get a measurement on the travel necessary to have the bolt completely close - little more than .050" but less than .060". This pic is supposed to represent the gap between the bolt face and the barrel/chamber with the new 77/22VMBZ complete trigger guard installed.

What do you guys think? Machine the back curved portion of the ejector abutment piece???

 

[Clay]

OK, ejector abutment modified

Bolt now closes like a charm! Modified the rear curved side of the ejector abutment - it is a really thick piece to begin with. Tried to keep the same contour using the Dremel tool. Worked perfectly. Using the old ejector abutment part from the synthetic stock as a comparison in the photo.

 

[Clay]

Rear view of the modified ejector abutment

from the rear ...........

 

[Clay]

Opened up the barrel channel ......

with a 7/8" wooden dowel rod and 400 grit fastened with contact cement .......

 

[Clay]

Barrel/stock forearm view

Dowel rod worked nice and evenly.

 

[Clay]

Top view

Everything sits in nicely!

 

[Clay]

And the side view .......

Magazine seems tight in the mag well, but everything is new with sharp edges; i.e. new magazine well parts and new Ruger mags!

 

[Educator]

Bravo...I for one (since I have been watching this thread with quiet anticipation) am glad you went with that option. I was worried you were going to start carving on the breech block. This is better than a soap opera.