I am in my final revision on the B mag, Today I picked up a stainless bull barrel I looked at 4 before finding one with bases that are true to the action. and cleaned out the boyds to fit the bigger barrel its all mounted up and ready to go to the range will report back with the results after barrel break in etc. on a side note if anyone has a original untouched stock for the thin barrel they want to sell please message me.
For me, I think the B.MAG issue is resolved. On 5/11 I went to the range with my accuracy-shooter friend. He and I shot at six different targets at 100-yards. I also had my Marlin 17HMR and we tried that, too. Over the course of the shooting session, we shot 28 rounds of the 25gn B.MAG ammo. What we learned was very interesting.
First, I was able to shoot groups typically about 1½"x2¼". My friend shot groups of about 1¾"x2½". Since he was totally unfamiliar with the B.MAG, I attributed his poorer groups to the fact that trigger feels was much different than his double-set trigger rifles he was used to. The conclusion I reached was, based on 18 shots fired by me and 10 fired by him, it is the B.MAG, not me that is limiting the accuracy. Both of us experienced some failures-to-extract
The photo below shows a 8-shot sequence; I shot that seemed to be fairly representative of the day for me. Notice that there are 4 bullets in the bullseye and 4 flyers. That seems to be what I've come to expect: some close, some wild, with no apparent cause.
We recovered all 28 spent cases. As we were picking them up, my fiend noticed that some had split cases. We looked at all the cases and discovered 10 split cases. The photo below shows the worst of the 10 cases that were split.
Now looking more critically at the targets we shot, of the 28 rounds fired, 10 were flyers. Ten flyers and 10 split cases? A coincidence? I don't know but I suspect a positive correlation between the case condition and the flyers.
I sent a lengthy photo-containing email to Savage. I their reply, they suggested I check the unfired ammo. I had 38 unfired rounds in one box that I examined carefully. One of the cases of the 38 was badly split at the neck, as shown in the photo below.
One or two other cartridges did show evidence of case splits--very fine cracks, difficult to see without using a hand magnifier.
But a large number of cartridge cases showed stress marks or 'incipient cracks' in the shoulder region. These were fine, tiny little linear lines that paralleled the length of the case. Too small to be easily photographed. These tiny 'cracks-ready-to-happen', in an imperfect chamber or with imperfect headspacing, will allow the case to split on ignition, thus causing the bullet to launch out-of-true with the bore resulting (possibly) in a flyer, and (possibly) a failure-to-extract.
If I were to pursue this, which I may not, would be to inspect each and every cartridge before firing and cherry-pick only the flawed free cartridges. Then, the accuracy tests might lend further light on the true accuracy of the B.MAG. I encourage each of you to carefully inspect the cases and use only the ones that are free of flaws.
Whether it's the B.MAG or the ammo, the net result is the same: the B.MAG cannot be depended upon to shoot good groups.
Last edited by oregonreloader; 05-17-2014 at 10:37 AM.
Reason: Manage photos
Well bull barrel is not a magical cure for accuracy, at least not yet I just wrote a big post and accidentally closed the window..any way I am getting consistent groups around an inch with random flyers. flyers seem to be tied to split cases about 70% of the time best group after 50 rounds best group was 3 shots within .5 inches and 2 left .5 measured just under an inch this was at 100 yards with gusty winds maybe 15 mph. most groups are 1 inch to 1.5 but they look like groups not shotgun splatter. Lost the target between the range and the house. I am bedding the recoil lug and first inch or so of the barrel might make it back to the range tonight if it sets up. picture of new set up to keep you interested
More on my b-mag saga. First purchased on 1/17, returned the stock without shooting as it was not free floating. Got second stock with same problem. Shot it and got best group of 4 inches @ 50 yds and split cases. Returned it to Savage and was told 6 weeks turn around. Called them 8 weeks later, and was told that they would replace it. I opted for heavy barrel(+$50) and was told 2 weeks turn around. Now three weeks later and just got off the phone with Savage. They say another 2 weeks before it's shipped. 4 months and still counting.
This thread now has 32 pages of posts that describe our woes, issues and minor claims of potential success (that never seem to come to fruition). We continue to be hopeful and look for ways to float the barrel, put vibration dampeners on the barrel, get more rigid bull barrels, and so on. But no one, as far as I can tell, has found the magic elixir that allows the B.MAG to shoot accurately, dependably and repeatedly.
I haven't tried to tabulate the number of yeah-sayers here--those among us who are entirely happy with the performance of their B.MAG--but my gut recollection suggests that the number of 'unhappy' shooters far outweighs the number of those 'happy' with the B.MAG.
I've spent a LOT of time since last September, going through several B.MAGs and hundreds of dollars worth of both 20gn and 25gn ammo. My last outing, reported in brief three posts up, suggests what might be the predominant and real cause for our problems: the ammunition.
Go back and look at my earlier post and click on the pictures so you can study the enlarged photos carefully. Then go look at your ammunition. And look at it very carefully, one by one, with a powerful hand magnifier. Never mind weighing each cartridge or polishing each one, or other useless tasks. Just look for defects in the cartridge case.
Look for obvious tears in the neck, just as shown above. Look for minute case cracks. And look all round the shoulder of the unfired cases for tiny--almost imperceptible--longitudinal lines that suggest metal fatigue. These are incipient case splits, failures to extract, and possibly, indications of pending poor accuracy.
If you find unfired rounds with any of these conditions, separate them (by symptom) from the other unfired rounds that do not show any problems. Then shoot them separately (by symptom) and record your observations for the separate symptoms and their groupings, comparing the symptom with the results you obtain with unblemished rounds. Then report the results here.
I have concluded that it is pointless to continue to hammer at the B.MAG itself, without considering the ammunition that we feed it and how that is affecting the performance we see. My experience is that the folks at Savage are good people and they are really trying to help us. But, it very well may be that it is the ammunition that is causing the problems we all complain about. And maybe--because of the Savage-Winchester partnership in the .17WSM venture--Savage just cannot publicly point their fingers at Winchester.
But if finger-pointing is justified, we can do that.