Gentlefolk,

I think I know what has happened, but wanted to bounce it off you, the experts, for concurrence.

My 13 yr old son enjoys shooting my WSM, so I've been making "light" loads for him to use both on targets and hunting. (I started with a "youth load" listed on the Hodgden web site.) These efforts have all been successful, to the point where I now need to get myself a new rifle.

My brother-in-law has whined the past two years about the bruises his 7mm Rem Mag gives him. So I offered to make some light loads for him to try. Using 115 gr Speer HPs, 130 gr Speer Hot-Cors, and 139 gr Hornady Interlocks with various powder loads of Accurate 4350 (in 56, 58, 61, 62 and 67 gr increments), I worked up about 50 rounds for him to try out.

Before I share more, I should state that he is shooting a Browning BAR chambered in 7mm Rem Mag. He returned from a short visit at the range, telling me that "these things won't shoot and they jam in my gun". He said the first round chambered and fired, but the second round did not fire and was almost impossible to remove. He added that the third round in his magazine did not fire either, and that he then loaded up 3 Federal rounds and had no problems with any of them.

I should add that all of the brass I used had been previously fired in his BAR. I simply neck sized them, ensured they had not stretched, and reloaded the "light" loads for him.

He showed me the 2 rounds that had not fired, and neither had a firing pin mark on the primer surface. At the time, we were at my house in a residential area, so I could not conduct a full test of his rifle and the reloads. But I ran a half dozen through his magazine and each chambered fully when pressing the bolt release.

My suspicion is that my loads were too light to adequately throw the bolt back with enough force to "cock" the firing pin after that first shot. I also suspect that the bolt did not then grab the head of the next round fully, and that may have had a part to play with his difficulty removing the other 2 rounds. Neither have any scoring on the bullet or the brass, so I do not suspect any difficulties entering the chamber.

Anyway, I am here simply to seek your concurrence of my analysis.

I next plan to work up some "light" loads for him by coming backwards, with reductions of powder charges until he is happy with the load, or until we start experiencing this same issue again. (Maybe I need to buy him a new rifle and he needs to give me his BAR. lol)

Thank you,
Martin

Martin,
I own and shoot a 7mm Rem mag in BAR. It has been my experience that the cases must be full length sized to fully seat in the chamber. My BAR is kind of finicky. If I try and close the bolt slowly (quietly) it tends to not push all the way forward and the gun will misfire. However it is simply because the bolt is not all the way forward. I would assume your problem is the case is a little too large to go into the chamber with only the spring forcing the bolt closed. The neck sizing works fine in a bolt gun but not so well in a BAR. I would try full lenght resizing and then work on light loads. Then you would be able to tell if the bolt is not being forced back enough like you mentioned. Hope that helps.
Ned

Thanks Nedley. Glad to hear of the idiosyncacies of this gun. He's come to me with the "bolt not fully closed" issue right after he purchased the rifle. I told him to always use the bolt release, even though it is loud, so that the bold slams forward completely. I had not considered my own words or that thought when I was working up the light loads for him.

I've not yet put the dies back in the turret, but my brother-in-law just returned from a "special" weekend hunt with additional information. I should add that he is a dual amputee and hunts from his chair. He chose to get the BAR because he felt working the bolt on a rifle is a little cumbersome for him. And he got a 7mm Rem Mag because his father uses a 7mm STW. He had never fired the STW or Mag before, so the recoil was quite a surprise to him.

Anyway, he went off to his hunt on Friday with a new box of Federal factory ammo. My father-in-law met him in MO for the "special handicapped hunt" on state land. My BIL said my FIL had found a box of Remington Managed Recoil cartridges in 7mm Rem Mag, so they decided to give 'em a try. (And no, they did not go to a range anywhere to try a few rounds before going into the woods.)

The first round chambered fine, as did each round. But he reported that after he made his first shot, the spent round was not thrown completely clear as the bolt pushed the second round in the chamber. Of course, he removed that spent case, but did not "slam" the bolt forward fully so when he attempted his second shot, it did not happen.

He said this happened twice on him, after which he put those MR rounds aside and used the Federal ammo for the rest of the weekend.

So while the BAR may like reloads to be full length sized, it may be that the BAR may NOT like a reduced powder load of any level. (He really needs to give me this 7mm and get himself a .243 or .270 BAR, or I need to be a good BIL and recommend he put a brake on his gun.)

Martin,
It seems that you have narrowed down your problem. Good work! I know that when I started reloading for my rifle I was cautioned to use faster burning powders (H4350), as not to cycle the bolt too forcefully. I however have used RL 19 and RL 22 for very successfully. The RL 22 tends to shoot the best but I don't load it to the max. I am about a grain under max for 160grn TSX. (I workded up the load according to barnes and backed off at pressure signs.) The problem I have found is that when the bolt cycles, it tends to give a shiny appearance to the case head. I think (I'm not sure) this is a function of the the extraction happening so shortly after the firing. Essentinally with a bolt gun if you see pressure signs (flat primer, shiny spots in the case head) you know that the pressure is too great. So I guess what I am telling you is that in the BAR, in my experience, this is normal. I get these signs at most powder levels. I.E. from the 10% below until max pressure. So, case head expansion is the only real way to measure the pressure signs. (once again opinion only.) To clarify, I don't get flat primers just the shiny case head. I could be out to lunch so take this with a grain of salt. I guess the point of this is that if you use a slower burning powder, you may be able to get the pressure needed to cylce the bolt at a lower powder level.
Another thought would be that maybe he has too much oil in the receiver. If the temperature is very cold it might hinder the action of the bolt. I find this hard to believe with the type of action and the pressure involved in cycling the bolt. I've found this to only be a problem with automatic shotguns and very cold temperatures. (Below freezing) I too have started to use the bolt release to load the gun as this tends to ensure the bolt is fully closed. Not to good for stealth but if the gun won't go boom, then stealth really is not an issue.
As far as recoil is concerned, my 7 mag is much more maneagable than my 30-06. The 06 is a much sharper recoil while the BAR is more forefull but not as abrubt. Also the blast is much greater, but I've come to expect it and it is no longer a factor. I do not have the BOSS system on my gun, however, that might help your BIL with some of the recoil problems. Although a true muzzle brake will make it unbearably loud.
I was told by my gunsmith that it is possible to not FL resize the brass, but it needs to be more than neck sized. He said he could measure a case for me and find out where to set the dies to get it to seat properely. I just haven't had the time or inclination to get this done. It shoots fine with FL resized cases. It is not a tack driver, but for an automatic it shoots just a little over MOA.
Good luck, I hope you get it worked out and your BIL has a successful hunting season.
Nedley

If light loads present a problem you might consider a in stock Mercury recoil suppressor, it will add a little weight to the weapon plus tames down the recoil, I got mine from Gamaliel, thier web site is http://www.gamaliel.com and the ones I recomend are the C&H Brand they are sealed no risk of leaks and no gunsmithing required, they just drop in the but stock screw hole and are easily removable, give them a try , and just shoot the full loads.

I have BAR in 300WSM and I would like to share with you what little I know about resizing cases for the BAR.
When a bolt gun is fired the brass becomes fire formed to the shape of the chamber. The handloader can then Neck Size, Full Length Size or Partial Full Length Size. When an auto-loader like the BAR is fired, the brass is not a "fired formed" case. The brass is usually much longer from head to shoulder than the chamber it was fired in. This is caused by the brass being extracted while still under a bit of pressure. Neck sizing this brass can cause all kinds of problems from jamming to slam fires to out of battery fires. It is important for the brass to be "Full Length Sized" when loading for auto-loaders not only for reliability but, safety.

Using the Stoney Point Head and Shoulder gauge I came up with the following numbers for my BAR 300WSM.

New Brass 1.736in
Once fired Brass 1.745in
Resized Brass would not chamber safely until I bumped the shoulder back to 1.740in. My die is set the measure 1.739in.

You are on the write track starting higher and working down to softer loads that will cycle. I do think you need to FL size the brass though.

SilentlySnoring:
Reloading for semi auto's is a bit different than for bolt rifles.
"never say never"
BUT NEVER NECK SIZE for a SEMI AUTO. The reloaded cartridge must be able to all but fall into the rifle's chamber. The semi auto's bolt dosen't have the camming power that a turn bolt action does. This can lead to erratic cycling of your action.
I use a L.E. Wilson chamber gauge to check my full length sizing die set up, and also check EACH completed round. This is a safety issue. I do not skip this step, even though I load several thousand rounds a year for service rifle competition.
The next issue is, does the reduced load have enough port pressure to properly cycle your rifle's action. The pressure in the barrel at the point where some of the gasses are used to operate the action is critical. If there isn't enough, the action will fail to cycle or cycle erratically. If there is too much pressure erratic cycling and or damage to the action can occur.
Just a couple thoughts.

muck

The BAR and 742/7400 I suggest using small base dies for resizing the brass. I use RCBS Small Base Dies which were made for the Browning BAR.