Suggestions To Help Me With My Centerfire Block Installation Problem

[Two Flints]

Hello SSS,

I'm almost there!  I re-worked my Spencer 1860 stock, filling in all the cracks and dings and it looks pretty good, if I do say so myself, well, at least a lot better than when I first purchased it from an 'old timer' here in Maine. 

I took it completely apart cleaned all the parts and then put it all back together with the original rimfire block.  Everything worked smooth, nice and easy, no problems...until, I tried installing one of the reproduction blocks.  Now, I have problems.

The repro block fits fine into the lower block with no rubbing.  When I re-install the block assembly without the spring, it still works fine, nice and smooth.  When I install the spring, either the original or a reproduction spring, working the lever/action assembly into the receiver becomes difficult, if not impossible to complete.  It seems to be because of the spring and how it pushes on the repro block???  By the way I've had the same problem with both the SS Block and the Buffalo Arms block.

I know this has been posted before, but would someone PLEASE state clearly how they modified their reproduction block so that it works in an original 1860 Spencer.  No short cuts, every step involved.

Thanks,

Two Flints

[Trailrider]

Hello SSS,

I'm almost there!  I re-worked my Spencer 1860 stock, filling in all the cracks and dings and it looks pretty good, if I do say so myself, well, at least a lot better than when I first purchased it from an 'old timer' here in Maine. 

I took it completely apart cleaned all the parts and then put it all back together with the original rimfire block.  Everything worked smooth, nice and easy, no problems...until, I tried installing one of the reproduction blocks.  Now, I have problems.

The repro block fits fine into the lower block with no rubbing.  When I re-install the block assembly without the spring, it still works fine, nice and smooth.  When I install the spring, either the original or a reproduction spring, working the lever/action assembly into the receiver becomes difficult, if not impossible to complete.  It seems to be because of the spring and how it pushes on the repro block???  By the way I've had the same problem with both the SS Block and the Buffalo Arms block.

I know this has been posted before, but would someone PLEASE state clearly how they modified their reproduction block so that it works in an original 1860 Spencer.  No short cuts, every step involved.

Thanks,

Two Flints

Howdy, Pard,

Because the spring is in front of the vertical stem connecting the upper block to the lever assembly, there may be enough play between the shaft and the hole in which it rides to allow the block to rotate backwards, binding the upper block on the receiver.  With no spring, the repro blocks are free to align themselves into the receiver. But with the spring pressure, the block is rotating backwards until it binds in the receiver.

Question 1: Do you have the original, rimfire breechblock?  If so, measure the diameter of the original stem and that of the repros.  If there is a signficant difference (I really can't tell you how much there can be) , you may have located part of the problem. The repro shafts are allowing the block to rotate to the point where it is causing the block to jam.

Question 2: Did you have to remove any metal from the repro breechblocks to get the block to fit in the receiver without the spring in place?  (While S&S stated that 95 percent of all Spencers would accept their block without fitting, mine was one of the 5 percent that did require that I remove metal from the repro block!) 

Question 3: Have you checked the headspace between the repro blocks and the barrel without the spring in place?  You can use cartridge cases and some brass shim stock (local hardware store should have either brass shim stock or automobile feeler gages).  If you have a number of cartridge cases, take the one with the thinnest rim and a .006" shim.  The breechblock SHOULD CLOSE on the minimum case and NOT CLOSE on the case plus the shim. If you can get headspace gages for .50-70 you can use the FIELD gage as the one one which the block should NOT close.

You will probably have to take metal off the REAR surface of the breechblock.  Use some machinist's dye or a permanent black marking pen.  Use a NEW mill file and VERY CAREFULLY file off metal about ONE or TWO passes at a time, filing until (a) you can get the block to work after installation WITHOUT a cartridge case and then WITH a case plus the .006" shim.  The marker or dye will show you where the block is rubbing on the receiver rails. File ONLY where the marker is, and then try it again.

If in doubt, have a competant gunsmith do this!

Hope this helps!

[Two Flints]

Thanks Trailrider,

You wrote in your post above the following:  Because the spring is in front of the vertical stem connecting the upper block to the lever assembly, there may be enough play between the shaft and the hole in which it rides to allow the block to rotate backwards, binding the upper block on the receiver.  With no spring, the repro blocks are free to align themselves into the receiver. But with the spring pressure, the block is rotating backwards until it binds in the receiver.

Well, what I did was to take out the spring and stretch it out just a bit.  This seemed to add  additional presure on the reproduction block preventing the play Trailrider mentioned in his post, and keeps it from binding when raising the lever into its closed position.  I tried the action about 20 times without any binding.  It's still not as smooth as I would like it to be, but what a big improvement from before.

Trailrider, thanks for the suggestion!

Two Flints

[General Lee]

Two Flints,
A center fire breech block! My God.  Are you planning on shooting that antique?
Only kidding I ordered one from GAD reloaders that would not fit regardless of how much filing I did.  The one I ordered from Buffalo Arms practically fell into place.  Now all I have to do is get the courage up to shoot it.  I was about to when I was kinda waved off by a number of members!
General Lee

[Two Flints]

General Lee,

What I did was to make a wooden vise for my original Spencer. Made it out of 2" x 6" boards.  The barrel fits through 2 round openings at the front of the vice, and the stock rests on the back part of the vice.  The Spencer is held in place on the vise with heavy bungi straps.  I have a wire that is attached to the trigger and by pulling on it, I can release the hammer and fire the Spencer from a safe distance, just in case. 

I have not attempted the firing yet...hopefully, within the next week or so, as soon as the weather and time permits.

Two Flints

[General Lee]

Two Flints,
I like the approach I was going to do something simiilar and inspect carefully afterwards for any evidence gas leakage.  My carbine "looks" very solid more so than newer firearms, I guess that is no garantee as to the condition of steel.  It would seem if it tested out ok it would be good with "standard" BP loads.  I would really like to shoot mine let us know how you make out.  I have GAD reloads  to try.
General Lee

[DJ]

There is often more to fitting the centerfire blocks than simply getting them into the lower block.  On both centerfire blocks I own (one marked "S&S" and the other unmarked, but looks the same as the S&S), the rear end of the groove in the top of the block was not quite deep enough and the block dragged against the forward end of the trigger plate when opening and closing the action.  It took me awhile to figure out what was going on.  I suggest painting them with machinist layout fluid, assembling, and then cycling the action to see where the contact points are. 

As far as S&S blocks being a drop-in fit for "95% of the Spencers," I can only say that neither block was a drop-in fit in any of the four Spencers I tried them in.