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View Full Version : Trouble benching the 45-70 BFR



44man
12-23-2005, 02:29 PM
I have posted before that the BFR 45-70 can not be shot as good from sandbags as it can from Creedmore. I see a lot more of you have bought them so I will show what happens. I have tried every way to rest the barrel on a bag with no luck. All of my other revolvers will shoot under an inch at 50 yd's with the end of the muzzle on a bag and the butt on another but not this one. It has shot under an inch at 75 yd's from Creedmore, as soon as the barrel touches a bag it goes to hell.
I made three tests with the 10 shots I took down. First five shots on the left target was with the barrel on a bag. I then rested the frame on the front bag, butt on another for three shots. These are the three in the bullseye and are at 15/16". I then repositioned the bags so I had to push the butt tighter in the rear bag to get on target and these are the two lower shots. This will show that any change in the bag tension under the butt will cause verticle stringing as it changes the barrel lift under recoil. The rear bag has to be exactly the same tension from shot to shot. It is better to put your hands only on the rear bag but with the long grips on the BFR it is hard to do.
Eliminating the rear bag and floating it on the frame makes it hard to hold steady even with the forearms on a bag.
Some kind of rest is needed for load workup or you are more or less shooting offhand. Nobody would do this with a rifle!
Even Creedmore is very hard to hold a gun steady.
I have tried the pistol perches and the recoil just blows them off the bench making getting back in position too much work. I have had the dumb thing flip over my head with the .475. Then the barrel on the 45-70 is still on a rest with them, no good!
Right now, the best way is a frame support and an even tensioned butt bag.

454PB
12-23-2005, 04:42 PM
Let me say up front that I agree with you on the fact that handguns need to be solidly rested for group shooting/load development.

However, I learned long ago that it is an unrealistic way to shoot. Yeah, I burned a lot of holes in sandbags doing what you are doing, but my experience has been that loads fired in that manner shoot to a different point of aim than when they are shot in a "field" position. It's sorta like shooting a rifle from a bench and resting the barrel, rather than the stock on the bag.

I rest my wrists on the bag. As you know from shooting hard kickers, you never know where the gun is going to go in recoil, I've had my hat kocked off and even my shooting glasses.

Granted, you are shooting tighter groups than me, but the point of impact is consistent using a wrist rest. It can also be reproduced in the field.

45 2.1
12-23-2005, 04:57 PM
I have posted before that the BFR 45-70 can not be shot as good from sandbags as it can from Creedmore. I see a lot more of you have bought them so I will show what happens. I have tried every way to rest the barrel on a bag with no luck. All of my other revolvers will shoot under an inch at 50 yd's with the end of the muzzle on a bag and the butt on another but not this one. It has shot under an inch at 75 yd's from Creedmore, as soon as the barrel touches a bag it goes to hell.
I made three tests with the 10 shots I took down. First five shots on the left target was with the barrel on a bag. I then rested the frame on the front bag, butt on another for three shots. These are the three in the bullseye and are at 15/16". I then repositioned the bags so I had to push the butt tighter in the rear bag to get on target and these are the two lower shots. This will show that any change in the bag tension under the butt will cause verticle stringing as it changes the barrel lift under recoil. The rear bag has to be exactly the same tension from shot to shot. It is better to put your hands only on the rear bag but with the long grips on the BFR it is hard to do.
Eliminating the rear bag and floating it on the frame makes it hard to hold steady even with the forearms on a bag.
Some kind of rest is needed for load workup or you are more or less shooting offhand. Nobody would do this with a rifle!
Even Creedmore is very hard to hold a gun steady.
I have tried the pistol perches and the recoil just blows them off the bench making getting back in position too much work. I have had the dumb thing flip over my head with the .475. Then the barrel on the 45-70 is still on a rest with them, no good!
Right now, the best way is a frame support and an even tensioned butt bag.

Have you tried resting the barrel lightly about at the end of the ejector rod housing and a slightly behind the wrist rest? I'm shooting a 41 mag Super Blackhawk with a 2 power scope this way. The crosshairs cover about 2" of target a 100 yards and is hard to see anything well, but this gives me consistent 2 1/4" groups at 100 yards. No other method of benchrest style of shooting will do this for me. Resting the butt on anything or crowding it would give what would be called a group.

doghawg
12-23-2005, 09:51 PM
.44 man

I use the method described by 45 2.1 for load developement. I don't let the grip touch anything or I ended up with the vertical stringing you experienced. To me, the key is to not put any downward pressure on the barrel, just a light enough touch on a soft leather pad to steady the scope. If I don't mess it up and if the gun is allowed to recoil consistently it will print 1" to 1 1/2" at 50 yards with 41 gr. of Rel 7 under a 405 gr CP WLNGC or 400 gr. Speer FN, which are the two best loads found so far.

Regardless of what the gun does off the bags, I verify my zero with a wrist rest only because thats how it will probably be shot in my deer stand. I suspect you have a lot more shooting and hunting experience than I do but this is what works for me.

Randy

Blackwater
12-24-2005, 12:03 AM
I also have found that letting the butt touch anything messes up my groups, especially with the Contenders. For revolvers or contender, I generally use my rifle forend bag with two smaller sand bags on either side, but up close, to rest my wrists on, so that the butt hangs out in the open. This is pretty darn steady when you get the setup right, but it IS a bit more challenging to set up right. I'll fiddle with the bags for 2-3 min. before getting them right, generally, but that's a well spent 2-3 min. in my experience. I do my load workup testing at 50 generally, and check at 100 or further by shooting from braced sitting with a back support, generally. That keeps me a mite more humble, and lets me know how the load will do on out there.

This works for me. Hope it helps some?

44man
12-24-2005, 01:11 AM
Yeah guys, I have tried everything with the 45-70 and any contact at all with the barrel blows groups. It shoots fair with just the frame on a bag and nothing under the butt however it is still hard to hold steady.
All bench testing is done just for load work. I always sight in for hunting from the Creedmore position. The strange thing is that both of my BFR's hit the same place from offhand, Creedmore or sandbags. The only two revolvers I CAN sight in from bags! Not so with my SBH and SRH, both of which have to be sighted without bags. I have tried the method of two bags for my wrists and it works pretty good. I blew a hole in my extra bag though, forgot where the muzzle was.
I have pretty much eliminated the verticle stringing with the butt on a bag. I just showed on my target what will happen when changing the pressure. If you notice, they didn't string and the two shots are still at 1", just lower. I would have had no problem putting them in the bullseye with the other 3.
Every revolver I ever owned or shot shoots the best with the end of the muzzle on a bag except the 45-70, this one is the exception. I can lay the side of the barrel against my leg in Creedmore with no trouble, but can't put it on a bag in any spot for the length of the barrel, with or without a bag in the rear.
The boolit I was using is from one of my moulds, weighs 330 grs and has straight sides on the ogive with a large meplat. I can hold around an inch at 50 yd's with it but it is not as accurate as my 317 gr boolit with a slight curve to the ogive and a slightly smaller meplat. Seems to be the same deal as the difference between a WLN and a WFN in my other guns. I am getting around 1535 fps with both boolits.
This BFR is very accurate, I have had five, 300 gr Hornadys touching at 50 yd's and had some loads up to 1800 fps with them. I can't drive the cast boolits as fast without hard extraction. I can use 4198 with the Hornadys but not with the cast. 4759 seems to work the best. I use 31 grs with the 317 gr and 31.5 with the 330 gr. Recoil is sharp and the gun is very loud, much louder then my shorter barrel guns including the .475. Cases fall out of their own weight. This powder also shoots the same at 90 degrees or 15 degrees outside.

Bass Ackward
12-24-2005, 06:41 AM
Well .... now you see I have learned something here.

I took one look at those BFRs and figured that you had to buy a trailer rig and shoot them from the cannon position. Go figure. :grin:

doghawg
12-24-2005, 11:05 AM
[QUOTE=44man
4759 seems to work the best. I use 31 grs with the 317 gr and 31.5 with the 330 gr. Recoil is sharp and the gun is very loud, much louder then my shorter barrel guns including the .475..[/QUOTE]

That was my experience with 4759 also. It shot well under a 405 gr. Rem (30 gr. charge) jacketed bullet but sounded like a 105 mm howitzer and the cylinder gap/muzzle flash ...... :holysheep ..... That was the only time the front of the frame was rested to shoot groups. I put a towel on my pistol rest to protect it and set it on fire 5 times in 5 shots!

Randy

44man
12-24-2005, 05:53 PM
Yeah, the stuff is like 335 powder! Really is accurate though. I shot my last deer near dark and the flash was something to behold. I can imagine what it would look like in the dark.

lar45
01-05-2006, 05:44 PM
I've shot mine with a sand bag on a 2x4 elevated rest about 10" up. I then rest the barrel with the frame at the back of the bag and nothing under the butt. I need a jacket under my right elbow or it gets sore. With this, I've shot under 1.5" at 50yds with open sights pushing a 405 to around 1750. The cylinder blast cut my bag up pretty quick and the wife just made me a new one. Maybe I should put some leather over it? I've shot mostly 4227. The slower powders didn't pattern well at all.