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kevin_stevens
09-21-2012, 06:46 PM
Working with my 116, I notice that the lugs on the bolt head itself do not align exactly with those on the lug collar(?) immediately behind it. There is a slight rotational misalignment between them as the bolt is worked. As the bolt comes all the way back, this causes the lug collar to strike the rear of the receiver, where it causes a bump in the bolt stroke as it is forced into alignment to be able to enter the receiver, or in the worst case the bolt stroke has hung up there and caused a short stroke.

Is this a timing and truing issue? And not to be rude, but if so, how do I get hold of Fred? I've sent two emails over the past couple of weeks asking to get on the waiting list, but no response to either.

And, just to be really dumb about this - what does that lug collar thing DO, anyway? It doesn't engage with anything, just rides back and forth on the rails and hangs up occasionally as described. What is its purpose?

KeS

earl39
09-21-2012, 08:06 PM
The best way to get hold of Fred is just keep calling. Lisa will answer emails but sometimes takes a while (as in a couple of weeks) because they are busy. The collar as you call it is there to help stop the flow of hot gas in case of a blown primer or ruptured shell. It is the front baffle. There is also a rear baffle right at the bolt handle. I would say the baffle is just a touch out of spec but nothing that can't be fixed.

kevin_stevens
09-21-2012, 09:06 PM
Well, the video on YouTube called it a lug. I know what the rear baffle is and it's purpose. I'll look the part up on Savage's site so I can explain better.

Tx!

KeS

BillPa
09-21-2012, 10:51 PM
Which part are you calling the collar?
http://i56.tinypic.com/23kcbow.jpg

kevin_stevens
09-22-2012, 01:14 AM
The front baffle. But only because it baffles me. ;)

So what I'm experiencing is that the front baffle isn't aligned perfectly with the bolthead as you draw the bolt back, and it hits the rear baffle. It's only off by a degree at most, and usually self-aligns from the impact of hitting the rear baffle. The net effect is a shock in working the bolt. Infrequently, the misalignment is enough that the bolt is actually stopped by the impact, leading to a re-rack or a short stroke depending on whether I realize what happened or not.

The bolthead itself always seems to be correctly aligned - I never have a situation where the front baffle clears the rear baffle smoothly and then the bolthead hits the rear baffle.

Thanks for the picture.

KeS

M.O.A.
09-22-2012, 02:11 AM
The rear baffle and the front baffle are both attached to the bolt and stay the same distance from each other I would say it's hitting the feed ramp

short round
09-22-2012, 02:36 AM
The spring washer may be oversize on the inside diameter causing it to catch on receiver or mag box. To check for this, remove spring from bolt & cycle bolt. these parts are available for about 10 bucks, from sss, midway, brownells, numrich.

kevin_stevens
09-22-2012, 02:54 AM
The rear baffle and the front baffle are both attached to the bolt and stay the same distance from each other I would say it's hitting the feed ramp

I'm sorry, that was stupid. Not the rear baffle - the front of the rear of the receiver. I'll post some pictures later tonight.

KeS

Update: Too dark to get good photos without blasting flash all over. I'll try tomorrow.

stangfish
09-22-2012, 08:59 AM
Articulating an issue without illustrations is not always easy. That is why you often see this ....


http://i1202.photobucket.com/albums/bb363/stangfish/dfc444b6_121054d1231181462-coral-star-dec-26th-jan-1-thread_is_worthless.jpg

sharpshooter
09-22-2012, 08:01 PM
What you are experiencing is more common on long actions than on short. The long bolt stroke combined with loose clearance around the bolt body lets the bolt assembly tip when you retract the bolt. With the short area of support around the rear receiver bridge, the bolt will not move in a perfect linear motion because it's being pulled by the bolt handle which is 2" off to the side.
The way you fix it: file the sharp edges to a bevel where the front baffle and the receiver opening are making contact so they deflect off one another instead of an abrupt halt.

kevin_stevens
09-22-2012, 08:49 PM
What you are experiencing is more common on long actions than on short. The long bolt stroke combined with loose clearance around the bolt body lets the bolt assembly tip when you retract the bolt. With the short area of support around the rear receiver bridge, the bolt will not move in a perfect linear motion because it's being pulled by the bolt handle which is 2" off to the side.
The way you fix it: file the sharp edges to a bevel where the front baffle and the receiver opening are making contact so they deflect off one another instead of an abrupt halt.

That sounds exactly like what's going on (pics uploading). And that was my thought - is it reasonable to get away with just filing the rear edge of the front baffle, or is that a hardened part (don't know why it would be)? Seems less drastic than filing on the receiver.

KeS

kevin_stevens
09-22-2012, 09:18 PM
Ok, here's a look forward toward the muzzle just as the bolt is leaving the forward part of the receiver. You can see the slight misalignment of the bolt head and the front baffle.

http://i1077.photobucket.com/albums/w475/kevin_stevens/Savage/IMG_0019_zpsdb1d85a9.jpg

Another view (that's grease on the rear of the baffle):

http://i1077.photobucket.com/albums/w475/kevin_stevens/Savage/IMG_0020_zps99427539.jpg

Baffle stalled trying to enter the rear of the receiver:

http://i1077.photobucket.com/albums/w475/kevin_stevens/Savage/IMG_0021_zps732eab09.jpg

Complete with cat hair! You can really see the offset well in this shot:

http://i1077.photobucket.com/albums/w475/kevin_stevens/Savage/IMG_0022_zpsb3e01be1.jpg

And bolt fully retracted into receiver:

http://i1077.photobucket.com/albums/w475/kevin_stevens/Savage/IMG_0023_zps3d3a0bee.jpg

KeS

sharpshooter
09-23-2012, 03:12 AM
The receiver is easier to file, the baffle is hard and you need a diamond file to break the sharp edge.

pdog06
09-23-2012, 06:15 AM
Does the baffle rub along the top of the magazine as it slides back? If so it could be raising the baffle and boldhead up just enough to hit the action.

kevin_stevens
09-23-2012, 02:21 PM
Does the baffle rub along the top of the magazine as it slides back? If so it could be raising the baffle and boldhead up just enough to hit the action.

Not noticeably. See the pics that show the misalignment as soon as the bolt starts back. And this happens with an empty mag.

KeS