My First Model 8 Update-Primer Issue Solved

[Wildgoose]

Got the rifle last week but due to work load had no time to start checking it out. Just got started last night. Other than the modifications to the but stock, wich were really well done but of course made the rifle worth quite a bit less, I have only found one other issue so far. The barrel jacket is very slightly loose. Not sure I am going to even try to fix it unless it gets worse with use. All else seems to be good to go. The bore is very good. Should be a good shooter. I will get some pics of the gun and strange butt stock mods soon. One quick question. I believe that the M8's did not have a firing pin rebound spring like the M81's. Is this true? My M8 does not have one. More later. Oh Yea, almost forgot, it is also fitted with after market sights. The front is a Marble's 57L with ivory bead and the rear a folding leaf with white dimond and adjustable for elevation. It was fitted with some type of tang sight but it is gone. I am looking for another one.

[81police]

the earliest 8's had neither a firing pin spring nor a firing pin buffer spring. Later 8's had both springs like the 81. Some 81's even have 3 piece firing pins in which a patent was filed for.

[Sarge756]

Wildgoose , You are correct about the 8`s not having a firing pin rebound spring.This , applies to the early models.Perhaps someone here knows the cutoff date that this changed on the 8`s. This question was relevant on an earlier post by ctgodog under "Headspace" where he was having a function problem and slam fire condition.Lots of replies to his post and he found that on his rifle someone had tampered with the trigger .He advised us that some file work to ensure proper sear and trigger hookup seems to have solved the problem. When I responded to him I noted that the slamfire condition could be due to a dirty /sticking firing pin and that a bolt tear down and inspection was in order.I neglected to mention that the lack of the rebound spring could also be a contributing cause. Another item should be mentioned and that is the method of charging the rifle. The slamfire condition is most prevalent when the shooter does not utilize the magazine and merely drops a round in the chamber and lets the bolt fly.Not hard to imagine that a sticking firing pin would do its business and give the shooter a big surprise.These rifles were designed to be magazine fed and you are taking some risk to let the bolt fly on any of them. Do your own investigation and drop a round in the chamber and let the bolt come forward slowly.It will not make full engagement without you manually pushing the bolt forward.Try the same with a round fed from the magazine and it should engage without you pushing on the bolt handle.This, like Mausers and others that are magazine fed, is due to the bolt picking up the round from the magazine at the proper angle and surrounding the case head with the extractor engaged as the cartridge moves into the chamber.If the round is in the chamber instead of the magazine the extractor has to ride up over the case rim to engage.Two negatives for this ; the mentioned possible slamfire and preventable wear and tear on the extractor.Have my suspicions that when folks have those broken extractors that this could be the cause. That part isn`t cheap if you can find one.
Joe

[81police]

Wildgoose,

Sorry I might be a little late in this conversation but If you are having slam fires I'd agree with those who already said to inspect the firing pin. I'll quote John Henwood on this one,

"any Model 8 or 81 which is in use should have its firing pin examined at regular intervals. The pin gradually becomes "mushroomed" at the back as a result of repeated hammer blows, and this will eventually cause it to jam in the bolt carrier or against the firing pin retaining pin. A slam-fire will result" (p.186)


regarding dropping the bolt with a cartridge already in the chamber,

"do not drop a cartridge into the chamber and release the bolt on it, as under certain (rare) conditions, such as a badly mushroomed firing pin head jamming itself into the rear of the bolt carrier, a slam-fire could occur" (p.202)

Hope this helps!

[Wildgoose]

As always thanks gentlemen for the excelent information. Below are pics of the butt stock mods. Like I said, well done by a home grown standard. I am sure that this rifle was '"comstomized" by someone marching to his own tune. Interestingly enough when I shoulder the gun my eye is in the perfict position that would have been right on for the peep sight. As I have said before these guns were tools and the folks that used them made the home grown mods to make them do what they needed them to do. As you can see a bolt inspection is under way. So far things look good. I am looking forward to the day when I can take a deer with this old hunter one more time. The stamp on this one says it was made in 1930. Eighty one years later it may well be on the way to still doing its job. Is this a great country or what?
PS: I will never again slip a round into the chamber and drop the bolt. Good advice that.

[imfuncity]

Like the home grown/costumization - stock and butt plate - indeed they were and still are tools.

[Sarge756]

Neat buttstock.A reverse cheek piece.Maybe he had a thick full beard and had to make room for it ? Glad you are making progress. Lots of shooting and lots of fun left in these old pieces of iron.It is a Great Country and we all hope our children and grandkids will be having similar discussions on some future forum. You are forbidden to post any more photos of your bench while it is that clean and tidy.How can you work so organized?
Joe

[DWalt]

These rifles weren't originally purchased by gun collectors, but for carrying around and shooting game. Therefore a little customization was often done. I've seen a lot of shortened stocks, lengthened stocks, crudely inlaid stocks, home-checkered stocks, painted stocks, rubber buttplates added, and many stocks with the former owner's name or initials carved into it. I bought a beautiful Winchester 73 rifle in .32-20 once that was in near-perfect condition, except for the initials W W carved in letters about 2" high on the butt, probably with a pocket knife. I always told people it formerly belonged to Woodrow Wilson. Who knows - maybe it did.

The same advice about not chambering a round and letting the bolt fly forward applies to other semis, such as the M1 and M14. While I have never had a slam fire, just as a precaution for the reloads I use in my M1 Garand, I use special CCI large rifle primers (#34) intended for use in the M1 and M14 rifles that have heavier cups which are more resistant to slamfiring. Even then, I ease the bolt down when firing single shots.

By the way, the earliest M16s had a slam fire problem also. I think the issue was that the firing pin was too heavy, and was later lightened to resolve the inertia problem. Initial attempts at solving this problem involved using heavier primer cups, but that led to unreliability during normal firing.

[Wildgoose]

Scored a Marbles R6 Tang Sight for the M8. Darn near paid as much for it as I did for the rifle. But its worth it to be able to put it back to the set up I think its past owener had it in. I am sure that the tang sight that is missing was not an R6 but it should function with the Marbles folding leaf rear and ivory bead front that was still on it. Not to mention my old eyes. I have the action all cleaned up and back together and when I am done with the bolt carrier and bolt clean up it will be time to take her for a spin.

[81police]

Don't take my word on it, but I think the extra hole in your receiver corresponds to a Redfield 102N receiver sight. Check out the link below...

http://www.gunbroker.com/Auction/ViewIt ... =254778593

[Wildgoose]

Don't take my word on it, but I think the extra hole in your receiver corresponds to a Redfield 102N receiver sight.

Wow! I do believe you are right. Even has the mounting screws too. Worth a shot.
Big Thanks Cam!

[imfuncity]

I had two M8's that were equal in almost every way, one with the Redfield receiver sight and the other with a Lyman or Marble tang sight. To me and my eyes the Redfield worked better, it stayed home when it was time to part with one of the rifles. Enjoy.

[Wildgoose]

Well...........Took the rifle to the range today for its first live fire test after cleaning and re-assembly. Good news first is that it functioned 100% and put the bullets where they were supposed to go using the open buckhorn rear sight. I did pickup that Redfield receiver sight but it was delivered while I was at the range today.


Now for the bad news. Four of the ten rounds fired had modestly backed out primers on them. These are factory Remington 150 grain SPs. So, seems that something is not as it should be. Not sure just now just what I am going to do. I am not really worried about shooting the rifle, as yet, so I may try doing a bit more testing with some reduced handloads and see what happens. Got to give this one some thought.

[Wildgoose]

I found an older post from about this time last year from a gent who had the same problem with an M8 in 35Rem. Seems it was caused by the shoulder of the cases being set back a bit too far. Factory ammo in his case too. Some close inspection on my fired brass indicates the same thing as well. When I get the set of dies I have on order I will do some resizing and see what happens. This explains the mystery of how some of the cases were backing out and others were not. On the cases that had the issue sure enough the shoulders are several thousandths back from the ones that were OK and this causes them to seat deeper into the chamber giving room for the primers to back out. Got to love this list.

[DWalt]

Absolutely correct. If cartridges are always going to be fired in the same gun, then neck sizing only is always best. That way, the cases are always fire-formed to conform perfectly to the chamber, and headspace differences between the chamber and the case are therefore zero. Also, your brass lasts much longer as it's not worked. Neck sizing is not a good practice for situations in which the same ammunition is to be fired in different rifles, or for some gas-operated semi-automatics, which are prone to causing stretched cases. Those cases must be full-length resized. For the Model 8/81, that is not an issue, as they are not gas operated and don't stretch cases upon extraction. In that respect, the M8/81 is much like a bolt action rifle, as the bolt remains locked to the barrel until all pressure in the chamber has been relieved.

I case neck-size only for my two 81's, one in .30 Rem, one in .300 Savage, and both work fine. All you have to do is back off the FL sizing die by a few hundredths of an inch from the shell holder. Or, you can buy a case-neck sizing die. I use one of those for my .220 Swift reloading, and the same die also works for .223 Remington. I have only one rifle each (both bolt actions) in those calibers.