Browning M71 short throat questions

[rando8586]

Apparently the M71 has a short throat or chamber, fired cases show markings on end of brass. Anyone else experienced this? Does it cause any problems? Cases trimmed a little short seem to work fine. Thanks Randall

[vancelw]

What kind of markings? Picture?
Are you sure it's not from ejection?

I've had two Browning 71s (still have one) and haven't had an issue with factory or reloaded ammo.

[Leverluver]

It definitely is short but I've never seen any marks on the end of the case. Mostly it shows when trying to chamber cast bullets with a full diameter portiaon ahead of the mouth. Sure you are not seeing a vestige of the factory crimp? Take a bullet and insert it in the mouth of the fired case. The bullet should slide in easily. If you feel any resistance to doing so, then you really do have a problem. There must be clearance to release the bullet and if the chamber neck is too tight or the chamber short (way too short), that could run up pressures.

[flatnose]

No. Not had that problem with my browning. What is the cartridge case length after resizing ? Trim after resizing, not before, as the necks will grow in length.
In order to get rid of the marks on the case neck, how much shorter than spec do you have to make the case oal?
Give the chamber a real good clean with solvent.
Pics would be good.

[jd45]

When you chamber a loaded round, do you see evidence of the rifling biting into the bullet? I did on my Marlin 336A in .35 Rem. with cast bullets, until I had a gunsmith throat my chamber. That corrected the problem in my rifle. jd45

[JFE]

I took a throat impression of my Browning and it has no throat at all. The chamber neck is a little long and this could be mistaken for a short throat. The jacketed bullets I load are a 2 diameter design and they chamber and fit fine when loaded to the cannelure. Only trouble I've had is with cast bullets, but even then if you use a Lee FCD to crimp the bullet in place so it clears, you can have good function and a really close bullet fit. I do the same with a 35 Rem and I think you will find most lever guns in traditional long rifle calibers have little or no throat. The pistol calibers and 375 Win are exceptions though.

[rando8586]

Case length 2.235,still make bright marks on the ends of brass,when loading a sized case.

[flatnose]

Randall, I would not load and fire the cartridges if they are showing bright shiney marks at the case mouth. It may cause problems with bullet release, and as lever lover says, it can increase chamber pressure significantly.
Your cases are already 20 thou under maximum length. and you can shorten them further until the marks on the case neck are no longer visible. If it was my rifle, I would probably do just that. Of course it will mean seating the bullets closer to the powder charge in order to crimp the bullet in place, so you will have to adjust the powder charge down accordingly.
If you take another 20 thou off the neck length, you will be approaching the length of the ackley improved 348 cartridge. Is it possible that someone has already set the barrel back and reamed the chamber to 348 ackley? That would explain a lot. Do you have any difficulty in resizing your cases?