Loading Sm*kless in Browning .40-65 BPCR?

[curator]

Web gurus point out that the Browning BPCR .40-65 chambers include a long freebore and oversize throat. Does anyone have any experience loading "white powder" with 300 & 350 plain base boolits in the Browning .40-65 BPCR? My Redding moulds both cast at .4105 using pure lead + 5% tin. Would this be too small and result in leading? I am wanting to use SR4759 since I have a few 5 pound jugs of it.

[Nobade]

I would make a chamber cast or impact impression to see exactly what you have. Size your boolit to no more than .001" smaller than the throat, whatever it is. As long as that boolit will still go into a fired case, you'll probably have great results. 4759 is about the ideal powder to use for that, so you should be in business!

-Nobade

[EDG]

I use SR4759 exclusively in my Browning .40-65. I got my data from Lymans data for 400 grainbullets. I started at 21 grains and worked up to 23 with a 320 grain bullet. The bullets that I shoot are .410. My groove diameter is .408. I get excellent accuracy and no leading.

[bigted]

yep ... Great advise ... my Browning is a 45-70 BPCR with the 30 inch badger 1/2 round/1/2 octagon barrel and I have been known ... SHHH ... to shoot the OTHER powder thru it from time to time. I also have been known to duplex with smokeless in it as well. my advise would just repeat what has already been mentioned so I will bring my spittle spewing to a stop!

[.22-10-45]

Hello, curator. Have you slugged your bore? I am shooting a .40-70 2 1/2" straight in an Axtell 77" sharps. These cases are nearly identical in capacity. I have used AA5744, H4895, and Varget. Bullet is a nose-pour copy of the Ideal 412263..the old .405 Win. bullet. Weight is 300grs. cast 20-1 tin/lead alloy. Bore slugs at .408 groove..I am using .410 dia. 100yd. accuracy is under 1" with vernier tang & sprit level globe front. Lyman has smokeless loadings for your .40-65 in their latest reloading book.

[curator]

Yes, I did slug my bore which is almost exactly .408. I did not make a chamber cast or throat slug as of yet, but plan on doing so. To refine my question, I should have asked it there was a information about these Browning .40-65 BPCR rifles having leading issues with .410 diameter soft lead bollits when loading smokeless powder. If they are known to have what the BPCR forum guys say; long. oversize freebore, that would be the case. I have a custom Greener Martini MkI .40-65 that I now load for using both smokeless and black powder loads. I was asking for information from other BPCR 40-65 owners about their experiences to determine if I can feed the same ammo to both of my .40-65 rifles. Simply looking down the bore doesn't reveal a long throat.

[Don McDowell]

[QUOTE=curator;2634352]experiences to determine if I can feed the same ammo to both of my .40-65 rifles. QUOTE]

The only way to find the answer to that question is to take a box of ammo, both rifles and head to the range. The target will answer that question in short order.
It's not real common for two rifles of different make to shoot the same ammo to the same level, but it's not unheard of either.

[montana_charlie]

I did not make a chamber cast or throat slug as of yet, but plan on doing so.

Simply looking down the bore doesn't reveal a long throat.
It appears that you already know your next homework assignment ...

CM

[EDG]

According to TexasMac - the Browning BPCR freebore is only .100 long

http://castboolits.gunloads.com/showthread.php?128691-browning-bpcr-accuracy/page3

[montana_charlie]

According to TexasMac - the Browning BPCR freebore is only .100 long

http://castboolits.gunloads.com/showthread.php?128691-browning-bpcr-accuracy/page3
Not to put too fine a line on it, but he said the freebore is almost double that ...

Concerning Browning .40-65 chamber dimensions, the chamber length is typically 2.123” and the throat has an effective freebore length of approximately 0.190” (front of the transition step to the start of the leade).

[bigted]

as I read this I see a couple questions ... 1- can I shoot smokeless in my browning 40-65 BPCR ... and ... 2- what diameter should I use to avoid leading.

as to the first ... I see NO reason to NOT use smokeless ... most especially the 4759. but RL-7 is another good one and of course black powder. just ensure that you load to no more pressure then the blackpowder loads give.

and the second ... the cheaters way ... at least the easy way to determine diameter to load with smokeless. measure the fired case mouth after removing any crimp ... take this measurement and subtract just enough ...[maybe .001 or .002]... to be able to finger seat a boolit in an unsized case. this will be the best diameter and along with loading your boolit out to engrave the rifling ... you should have no problems at all getting the accuracy you desire.

ideally what I desire is to have the case NOT swell any upon ignition. I want the case to pretty much remain unchanged when the powder ignites and the pressure starts the boolit on its journey. if there is no expansion needed to seal the chamber ... and the boolit has no place to expand ... and the only rout is to begin its forward travel ... then IF the boolit is already engraving the rifling ... it has no place to provide gas to bypass the boolit AND all that pressure will be contained to push your boolit straight down the tube and allow no yaw nor crooked tipping at the beginning of its forward travel as a result of ... "no place to go but straight ahead"

whewww !!!

[boommer]

The Brownings chambers in 40-65 are longer in with they will take a 45 -70 case sized down to 40-65 and not have to be trimmed. Starline cases are to short.The browning chamber length is
2.058 inside case rim and case length over all is 2.128, there is also a necking in that chamber it's a straight cylindrical from the case mouth 0.500 back you will see it on fired cases. The free bore is 0,100 and the effective free bore is 0.192. The Browning chamber is like a like a Ron Long chamber but it has a slight neck, better neck tension. Starline cases if used will make it seem like a crazy long free bore if used ! and not check your chamber length.

[bigted]

I also reform 45-70 cases into 40-65. my experience is that in the reforming process ... the 45-70 cases lengthen so as to need to be trimmed to your chamber. in your rifle ... all that is needed would to keep trying your reformed cases and trimming them till they just do chamber. then fire form em and retrim em so that they just do fill the chamber.

now loading cases so that the boolit engraves the rifling will net you the best accuracy IF you fill the fireformed case neck with the diameter of your boolit as well.

[boommer]

Yes Ted but on the Browning chambers in 40- 65 the 45-70 Win cases and RP cases they are still a couple thousands short after sizing and firing and with the necking you really don't want to size them after firing if you don't have to. My Browning BPCR 40-65 after the first firing my chamber allows me to just barely flare the case and slip fit a .410 bullet in the Winchester cases and just roll the flare in.

[EDG]

This is a quote from the legend of his drawing
"F is the freebore length, which is typically 0.100" but can run a little longer."

Montana Charlie - do you care to quote ?



Not to put too fine a line on it, but he said the freebore is almost double that ...