My fireforming load is listed above (post #115). It is giving me good, sharp shoulders. After that, I am using the bushing die with a .364" bushing and bumping the shoulder back 0.002". When loaded as above (post #125"), they chamber with no resistance.
338 Mega
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My fireforming load is listed above (post #115). It is giving me good, sharp shoulders. After that, I am using the bushing die with a .364" bushing and bumping the shoulder back 0.002". When loaded as above (post #125"), they chamber with no resistance.
Got to the range again today to shoot my ladder of 250 grain Nosler ABs and 6.5 Staball powder.
What I am seeing with this powder is that it is hard to get the SDs down and either I am at the low end of what it capable of, or it doesn't give the velocities that are reported.
I was only able to get 2606 fps with the 70.0 grain load. I didn't have pressure signs, but that is about 150 fps lower than what this bullet should be going out of my barrel, based on what I am getting with the 225 grain ABs using N550.
I guess I will have to try some H4350, H100V, and some N550 to see if I can squeeze a bit more out of the 250s.
I did confirm the 2925 fps load of 71.5 grains of N550 under the 225 grain Nosler AB will be my hunting load for now. Was able to shoot a 10-shot group that measured 0.863". I took it out to 300 and printed a 1.974" 5-shot group.
What I am seeing with this powder is that it is hard to get the SDs down and either I am at the low end of what it capable of, or it doesn't give the velocities that are reported.
I was only able to get 2606 fps with the 70.0 grain load. I didn't have pressure signs, but that is about 150 fps lower than what this bullet should be going out of my barrel, based on what I am getting with the 225 grain ABs using N550.
I guess I will have to try some H4350, H100V, and some N550 to see if I can squeeze a bit more out of the 250s.
I did confirm the 2925 fps load of 71.5 grains of N550 under the 225 grain Nosler AB will be my hunting load for now. Was able to shoot a 10-shot group that measured 0.863". I took it out to 300 and printed a 1.974" 5-shot group.
Got to the range again today to try the N550 load with the 250 grain Nosler ABs.
I was only able to shoot two of the 4 loads as I was starting to get stiff bolt lift on the second.
ADG brass, Rem 9.5M primer, VV N550 powder, 250 grain Nosler Accubonds
67.0 grains - 2665 fps, 8.3 SD (really good 5-shot group)
67.5 grains - 2690 fps, 6.4 SD **beginning stiff bolt lift**
68.0 grains - DNS
68.5 grains - DNS
I also set my zero on the 225 grain AB load. I think it will be just fine. For reference that is a 1.5" target dot. The shot outside the main cluster was my 5th shot and I was fighting a bit of mirage and the guy next to me blazing away with a braked AR.
I was only able to shoot two of the 4 loads as I was starting to get stiff bolt lift on the second.
ADG brass, Rem 9.5M primer, VV N550 powder, 250 grain Nosler Accubonds
67.0 grains - 2665 fps, 8.3 SD (really good 5-shot group)
67.5 grains - 2690 fps, 6.4 SD **beginning stiff bolt lift**
68.0 grains - DNS
68.5 grains - DNS
I also set my zero on the 225 grain AB load. I think it will be just fine. For reference that is a 1.5" target dot. The shot outside the main cluster was my 5th shot and I was fighting a bit of mirage and the guy next to me blazing away with a braked AR.
ruby76
Well-Known Member
Have you tried large rifle primers yet? Seems for a few of us that it lowers pressure and can gain speed by increasing the charge.
Tidesloe
Well-Known Member
If you've got any N560, you might try that as well. Seems to be pressuring out early. Even a little slower single base powder might give you better velocity.
It's shooting good though. Nilgai medicine!!!
I haven't. I am going to pull these bullets and load them up in the same powder charges with LR primers. I will also try a different, slower powder. The 6.5 Staball didn't give the velocity I was looking for. I would be happy if I can get near 2700 without the stiff bolt lift.
Tidesloe
Well-Known Member
I have a question for you 338 Mega shooters. I have one that is giving me problems and I'm looking for the source of the problems. It's seemed that my neck shoulder junction isn't forming like it should to my chamber, but possibly it's forming like it should. I had expected more of a sharp transition from shoulder to neck, but after 3x fired brass is coming out with a curved radius in that junction I'm wondering. I'm having to bump my shoulders back .006 to chamber brass and I'm speculating that if that transition should be sharper, maybe that's why I'm having to bump so far. After bumping so far that junction looks better, but after firing it's more curved again making me wonder if my chamber doesn't match my sizer die. I pulled my barrel last night, and looked at it, and I'm gonna cast my chamber one evening this week. I was planning on casting my die also but thinking being a bushing die, that alloy might flow between body and bushing. I don't know, we'll see sometime this week. Another think is, this rifle is shooting much worse than any rifle I've ever shot.
I'm attaching a pic of 3x fired, unsized brass. Does this look normal in the neck/shoulder junction area? It could be that this is normal. If so I'll go back to the drawing board. I'm looking at other possibilities also is why I've pulled the barrel and planning on casting the chamber. There is another symptom as well, but I won't go into that. I just need to know if this brass is forming correctly. Another thought is how can a reamer cut a chamber wrong? Doesn't seem like it can, so there is that.
I'm attaching a pic of 3x fired, unsized brass. Does this look normal in the neck/shoulder junction area? It could be that this is normal. If so I'll go back to the drawing board. I'm looking at other possibilities also is why I've pulled the barrel and planning on casting the chamber. There is another symptom as well, but I won't go into that. I just need to know if this brass is forming correctly. Another thought is how can a reamer cut a chamber wrong? Doesn't seem like it can, so there is that.
Attachments
Well, my 338 Mega has blood on it now. Took it to our annual company Nilgai hunt on the Yturria Ranch in South TX. Was able to kill a Nilgai bull, a Nilgia cow, three pigs and a coyote with it. Using the 225 grain Nosler Accubond load that I posted about earlier, it went 6-for-6 on shots at game. The only one I missed was at a group of running pigs at just over 200 yards. The reason it is still a 6-for-6 ratio is that I was able to double on another group of pigs. The bullet entered the rear right ham of a 125-lb sow, traveled the length of the body, exited just below the left eye and broke the hip of the 150 boar that was standing behind her. A quick follow-up with the guide's 22 mag put him down for good, but he wasn't going anywhere. The other pig was a 250 yard shot with the bullet impacting in the neck for an insta-kill. I was aiming for just below the ear, but he took a step at the shot. The coyote was at 82 yards, running across the road. Hit him mid body and pretty much split him in half.
The Nilgai bull shot was 124 yards. He was in a fenced off portion that they try to keep the cows out of, so it was pretty grown up. He had been spotted back in there over the last 3 years, but nobody had gotten a chance at him because 1) there is no way to get a vehicle back in there if you do get one down, and 2) this particular bull had a habit of getting into the bush quickly, so even if he was up closer to the road, none of the other clients could get a shot at him. We spotted him about 250 yards from the fenceline about 15 minutes before dark. We drove past by about 100 yards and hopped out to see if he was still in the open. Since we had 12 people in our party, the guide was pretty sure that if I was able to put him down, we had enough people to drag him to the fence so we could load him on a truck. When we got back to the fence, he had alread slipped into the bush. He was a cagey one. We were able to spot him about 20 yards into the bush. He was standing still looking back in our direction. After about 5 minutes, he started moving. He walked about 100 yards, but there was no shot opportunity. I spotted a little window in the brush that I told my guide I could shoot through if he stayed on the same path. Just as it was getting too dark to see him, he finally made it to that spot. Right as he stepped into it, my guide did a little cough and he stopped. I had about a 5" window to shoot through and only had the head/neck available. I hit him just below the white patch and he went 1.5 yards, straight down.
For my cow, I wanted to take a longer shot, so the group of us drove out to spot where there was a large open pasture with a water tank (water hole) in one corner. The guide said it was a place where they like to come out and feed in the mid-morning as the temps start to come up. As we were walking down the road to get there, we started to cross a perpendicular cut. The guide froze and motioned for us to stop as well. When I looked through the brush, I could see that there was a cow standing in the cut about 18 yards from us. She had been facing away when he hit the opening. She slowly walked into the bush and he started to set up the shooting sticks (Rudolph sticks, for any that haven't used them) and motioned for me to get set up on the sticks. Just as I stepped into the cut, another cow stepped into the cut at 42 yards. I didn't even get on the sticks, I just pulled the gun up and shot her, off-hand. She jumped about 6 feet straight up and started to tip over, but when her feet touched the groud she bolted. We heard her pile up. The other guys came up to us and we all went into the bush where she had entered. About 2 yards in, we found a blood trial (which is not very common for Nilgai) and followed that for about 25 yards, where we found her piled up.
All-in-all, I am very satified with the performance of this round on some pretty tough critters. None of the bullets stayed in the animals, so I don't have any weight retention numbers, but considering the farthest any of the animals went was 27 yards, I am happy with the bullets as well.
The Nilgai bull shot was 124 yards. He was in a fenced off portion that they try to keep the cows out of, so it was pretty grown up. He had been spotted back in there over the last 3 years, but nobody had gotten a chance at him because 1) there is no way to get a vehicle back in there if you do get one down, and 2) this particular bull had a habit of getting into the bush quickly, so even if he was up closer to the road, none of the other clients could get a shot at him. We spotted him about 250 yards from the fenceline about 15 minutes before dark. We drove past by about 100 yards and hopped out to see if he was still in the open. Since we had 12 people in our party, the guide was pretty sure that if I was able to put him down, we had enough people to drag him to the fence so we could load him on a truck. When we got back to the fence, he had alread slipped into the bush. He was a cagey one. We were able to spot him about 20 yards into the bush. He was standing still looking back in our direction. After about 5 minutes, he started moving. He walked about 100 yards, but there was no shot opportunity. I spotted a little window in the brush that I told my guide I could shoot through if he stayed on the same path. Just as it was getting too dark to see him, he finally made it to that spot. Right as he stepped into it, my guide did a little cough and he stopped. I had about a 5" window to shoot through and only had the head/neck available. I hit him just below the white patch and he went 1.5 yards, straight down.
For my cow, I wanted to take a longer shot, so the group of us drove out to spot where there was a large open pasture with a water tank (water hole) in one corner. The guide said it was a place where they like to come out and feed in the mid-morning as the temps start to come up. As we were walking down the road to get there, we started to cross a perpendicular cut. The guide froze and motioned for us to stop as well. When I looked through the brush, I could see that there was a cow standing in the cut about 18 yards from us. She had been facing away when he hit the opening. She slowly walked into the bush and he started to set up the shooting sticks (Rudolph sticks, for any that haven't used them) and motioned for me to get set up on the sticks. Just as I stepped into the cut, another cow stepped into the cut at 42 yards. I didn't even get on the sticks, I just pulled the gun up and shot her, off-hand. She jumped about 6 feet straight up and started to tip over, but when her feet touched the groud she bolted. We heard her pile up. The other guys came up to us and we all went into the bush where she had entered. About 2 yards in, we found a blood trial (which is not very common for Nilgai) and followed that for about 25 yards, where we found her piled up.
All-in-all, I am very satified with the performance of this round on some pretty tough critters. None of the bullets stayed in the animals, so I don't have any weight retention numbers, but considering the farthest any of the animals went was 27 yards, I am happy with the bullets as well.
