Difficult chambering

[bear-kodiak]

Hello list
This is not Shiloh related and if out of bounds please
accept my apologies and delete
this post. Took my new 45-70 Uberti Highwall out to the range today.
I found I had trouble chambering the round. It would go in all but the last 1/4 inch.
I had to push really hard with my little finger to get the round in.
I was able to shoot off about 20 rounds this way.
Thinking I may have not resized the brass all the way, when I returned home
I tried inserting a brand new fully resized unloaded cartridge. Only to have
the same trouble. I did notice very faint scratches at the base of the shell.
Would welcome any and all help from you guys. Thank you in advance...Jim

[Kurt]

If your full length sized case is tight that it needs a hard push to fully seat it I would cover the case with Dykem or if you bout have that use a felt tip marker and coat the case and carefully chamber that case trying not to rub the sides to see where the tight problem is.
If those cases have been shot in a different rifle that chamber might have been on the generous side and the base of the brass swelled for that chamber.
If this is the case maybe some new brass or cut the EZ edge off the base of the sizing die so it will size the case base down.
This is something I had to do for my .40-70 Shiloh using the .405 Win brass so it would chamber.

[mdeland]

Sounds like a tight chamber cut with a minimum spec finish chamber reamer from the factory. You have two options that I see.
1. Send it back to factory for correction after first trying a factory loaded round to see if it will seat properly. If a loaded factory round will seat properly they probably won't take it back in warranty but it doesn't hurt to ask. If a factory round seats without issue then your probably messing up in your case resizing some how. Some times the throats are to short and will need lengthening to work with cast bullets but this is easily corrected with a throating reamer and some hand or fire lapping.
2. Keep it and Lapp the chamber a bit bigger and smoother with a fire formed case. To do this you remove the primer and drill and tap the fired case primer pocket hole to 1/4 x20, thread in a rod for a axle to be inserted in a hand drill motor. The case is charged with lapping compound and the chamber is enlarged by slowly rotating the case in the tight chamber. It needs to be moved in an out a bit but do not lengthen the chamber by pushing the underside of rim against the chamber face seat. You want to enlarge radially but not lengthen it to keep your head space tight.
The trouble with using another finish reamer is it will often leave a step on one side or the other if the new pilot does not fit the bore closely. If a new chamber is to be reamed the best way is to set the barrel back so your cutting fresh steel on all sides. This of course gets into a new breech face cut, extractor fitting, fore arm dovetail move and forearm refit.
Lapping is the safest and easiest route if you plan on fixing it yourself.

[bear-kodiak]

Thank you for the 2 reply’s.
Right now I don’t have any factory rounds.
What I do have is new unprimed factory brass, and with them I have
the same problem....Jim

[John Boy]

Pushing the round with finger to seat it is an indication the bullet ogive needs to be shoved more into the leading bore cuts. The COL of the reload is too long and a magic marker from the bullet nose to the rim will show you where

[bear-kodiak]

[quote="John Boy" post_id=321317 time=1605919170 user_id=218781]
Pushing the round with finger to seat it is an indication the bullet ogive needs to be shoved more into the leading bore cuts. The COL of the reload is too long and a magic marker from the bullet nose to the rim will show you where
[/quote]

Thank you John, this happens with an empty case too....Jim

[Coltsmoke]

What sizing die are you using? The sizing die is probably what scared the case. I ran into this using a RCBS die, had to use a Redding die to solve the problem, it sized the case right at the base just a tad smaller than the RCBS die, problem solved, this was with a 40-65. Check the small scratches on the case there might be small pieces of the brass sticking up that is not letting you chamber the brass.

[bear-kodiak]

[quote=Coltsmoke post_id=321319 time=1605920578 user_id=53745]
What sizing die are you using? The sizing die is probably what scared the case. I ran into this using a RCBS die, had to use a Redding die to solve the problem, it sized the case right at the base just a tad smaller than the RCBS die, problem solved, this was with a 40-65. Check the small scratches on the case there might be small pieces of the brass sticking up that is not letting you chamber the brass.
[/quote]




I’m using a Lyman sizing die. Older variety , their in a red plastic box....Jim

[bear-kodiak]

[quote=Coltsmoke post_id=321319 time=1605920578 user_id=53745]
What sizing die are you using? The sizing die is probably what scared the case. I ran into this using a RCBS die, had to use a Redding die to solve the problem, it sized the case right at the base just a tad smaller than the RCBS die, problem solved, this was with a 40-65. Check the small scratches on the case there might be small pieces of the brass sticking up that is not letting you chamber the brass.
[/quote]

I’m using a Lyman size die. An older variety which came in the red plastic box...Jim

[Coltsmoke]

Check with your shooting buddies see if anyone has a Redding die you could borrow, if not, you may have to buy one. I saw a list one time on this forum showing which dies was the largest and smallest, good luck finding it, but the Redding was the smallest.

[mdeland]

In my opinion fix it right don't keep putting up with an undersize chamber as it will be a pain in the keester to reload for from now on. If the body is to small for sized cases then the necks probably will have to be reamed thin to accommodate the proper bullet diameter fit into the barrel groove. Guess you could shoot bore diameter PP bullets though if you can seat them in the undersize cases.
A tight chamber as in match chamber is a different animal from a chamber cut with a reamer that is below minimum spec for the cartridge design being used.

[powderburner]

You said cartridge, did you mean empty case if it was the cartridge you may be deforming the bullet. if it’s just the empty case then maybe you could cut 10th a 10th of an inch off the die.

[Clarence]

You can try Powderburner's suggestion without modifying your die this way: Back off the die by 1-1/2 turns (~0.090") and remove the depriming rod, lube your case, set it on top the shell holder, and push it into the die. You will need to use a brass or steel rod to tp the case out of the die. If it then chambers properly, removing material from the base of your die and running all your cases back through the sizer will solve your problem. you will need to do this only once for each case. Purchasing the tighter Redding die should also work.

One thing bothers me: when I ran into this problem while forming .40-65 cases from .45-70, there was no pushing it in by 1/4", so check the chamber for scratches as well.

Clarence

[bear-kodiak]

Ok, as an update. Today I purchased a box of Hornaday factory ammo
to see if I still had the same issue. Upon trying the round still needed to be
pushed in the last 1/4 inch.....Jim

[Coltsmoke]

Now it sounds like you have a chamber problem.