[CPC]

Since I been getting a bunch of 10/22 bolts in here that have the Bolt Chamfering modification already done to them, Im now wondering if there is any drawbacks?.. Has anyone noticed any new problems after chamfering the back of the bolt?

I can chamfer the bolt upon request with the normal CPC Bolt Combo work, but I am serious about checkng it out first... I guess, My worry is not about std vel ammo or sub-sonic, but High Velocity ammo use...

 

[050]

I don't know exactly how many rounds I've ran through mine since I did it, but so far, it hasn't had a hickup in what I'd guess about 500 rounds total of WMT, Lapua, and Remington Golden bullet HP's. Maybe 200 of the Rems.

That's not a lot, but so far, so good.

Ron

 

[yellowfthr]

bolt chamfering

I have more than a 1000 rounds of the Federal High Vel. bulk through mine, as well as a larger no. of the better stuff. I have barely a mark on the chamfered area. Would definately do it on my next bolt.

 

[Pinball]

Randy,
All mine have been chamfered for about 2 yrs.I don't shoot a lot of high velocity stuff.But I have never had any problem from any of the 3.My smith doesn't like it for his 3 rifles.He says it causes the rear of the bolt to move upward and strike the receiver.But I can find no damage or harm to mine.I personally think it makes the bolt cycle a little quicker.I did mine for more reliable and consistent cycling with match/target ammo.I think it helps.
Mike

 

[050]

Pinball...

When the bolt starts back, initially, it hits the hammer at about a 90 degree angle. As the hammer pivots back, the bolt will attempt to ride up on on the angle the hammer presents.

It will do that regardless of whether you have a stock bolt or a chamfered one. I believe your gunsmith needs to take another look at his reasoning.

The cold hard fact is, since the bolt hits the hammer higher, it has more leverage to push the hammer back. In effect, it will actually have LESS of a tendency to ride up, merely because of the mechanical advantage. He's looking at the situation basackwards..

Ron

 

[395]

Champhering....

No worries about it Randy! It's a great mod. I've put PLENTY of rounds through my 10-22's. Three of them . All have champhered bolts, and have probably seen about over 9000 rounds total on all three rifles since it was done. Run High Vel stuff, including CCI stingers very well, and with Dakotan's buffers in place, I have no worries about the lifespan of the rifle. If anything, I belive the champhered bolt has aided reliability with all ammo types. Just my opinion though.

Sincerely,
GAU-2

 

[Ohcsim]

Randy,

From your note, I guess you've received the bolts I sent you for your "control-pin" upgrade as I chamfered both of them a while back after hearing only upside opinions on it.

I used the belt-sander method and, although EZ-enough to do, I think they both still need a little "squaring" which I'll attempt after you're finished with them.

Of course, if you should choose to offer chamfering as an option in the future, I (as one amateur) will retire from the field and let the CPC experts take over :t .

Keep up the good work,


Ohcsim

 

[Tenspot]

Randy,

I did it to one of mine, no problems so far, and it does cycle nicely!

I have shot about 100 Velocitors through it and had no problem (cept they impacted 5 inches higher

 

[D.Stewart]

Randy,

Speaking of chamfering. What would be the cost of a Full Tune-Up, with the chamfering, on a brand new 10/22 LR Deluxe Sporter.

Thinking about getting one. I'm going to be lazy this time and pay a real proffesional, you, to do the work, if you don't mind.

Thanks,

Derrick

 

[CPC]

Thanks Antlura, Yellowfthr, Gau-2...


Pinball, I think like your gunsmith, we operate under the concern "that for every action there is going to be a equal re-action"... So we are slower, than we watch for the re-action, than we change, heha... The Ruger patent describes a delayed blowback, which means when the bolt goes all the way back and contacts the bolt stop pin, since the bolt stop pin is lower by appox .020, the rear of the bolt is to drop down to engage pin... So when using the original steel bolt stop pin the bolt chamfering modification would have no adverse effect since the pin has momentary control and is the guide...

A 10/22 shooting High Velocity ammo tends to send the HAMMER all the way back until it contacts and stops on the aluminum trigger guard... So, what I am looking for is if the hammer is smacking/smiting the aluminum casting much harder when the bolt has been chamfered?

Smudging alittle aluminum back there is no problem, all 10/22s do that, but I seen enough hammers get stuck in the aluminum and fail to come forward... Stuck... (All had cut hammer springs to lower trigger pull weight)...

Ohcsim, no problem, yours look the best that I have seen... (I know, you did not think the 10/22 was such a complicated mechanism, heha)

(So Im am getting bolts in for the CPC Bolt Combo work that have been chamfered... I am not seeing chamfered bolts in 10/22s that are being sent in for Tuneups... So Im not getting to see the trigger groups and receivers, so thats why I posed this question)...

 

[3192]

Mine

Mine and Mayo's should get there any day now. Both are Chamfered and neither have had any problems. I have about 4,000 rounds through the one that says DM on it. I give Chamfering :t :t

D

 

[050]

I agree with Antlurz 100%. Once the hammer is pushed back and close to the cocked position, it pushes the bolt upwards regardless of whether it's chamfered or not. The main thing is that a chamfered bolt attacks the hammer higher from the pivot point so it takes less force to cock it. It's just a law of physics.
A new bolt buffer is a must, due to the bolt recoiling faster because of less resistance from the hammer. I would replace the bolt buffer with a Dakotan buffer regardless, whether I chamfered the bolt or not. Bill

 

[rc.]

I can think of but one problem that may crop up with a more than mild bolt chamfer. The bolt depresses the hammer and sear to prevent auto fire. If you chamfer too much, the trigger may reset a split second too soon and the hammer may ride forward with the bolt instead of a split second later and may take some of the oomph out of firing pin hits during rapid fire. In a target rifle it's no big deal because there is plenty of time between shots, but in a rapid fire plinker it MAY cause an occasional failure to fire. I do feel that polishing the contact surfaces will slick the action but to overdo the chamfer may have negative consequences.

 

[050]

Randy....

Here's another point to consider about the hammer being thrown back.

The chamfered bolt will, at a given recoil speed, push the hammer back slower than a non chamfered bolt, since the contact point is higher it automatically is moving the hammer slower because the contact point distance to the pivot is greater... Just another example of the laws of physics.

As to the subject of it being lighter so it moves faster, that's also true, however, here again it's all physics, and the percentage of difference in weight is no where near the percentage of difference in leverage resulting from the modified bolt. (I'm making that statement on the basis that the chamfered bolt is done reasonably similar to the dimensions of the one I pictured in the Tips and Trick article)

Using a very high, sharp angle on the chamfer like in that photo should result in hammer travel that is a LOT slower (referring only to the movement of the hammer, not the speed of the bolt), whereas the stock bolt contacting the hammer down low results in a violent immediate slamming of the hammer to the rear.

Ron

 

[CPC]

Good points, all...

 

[698]

Randy

I first read about bolt chamfering (and lightening) in Mark White's book, The Ultimate Ruger 10/22. You might check it out. It's a good reference book.