I would be surprised if there were not enough interest. There might be another reason. The Deep South ELR matches are filling up 30 light gun slots within minutes of opening.
New Berger 375 bullet 410 hybrid
- Thread starter Sleepertruckguy
- Start date
Ha. Yeah I am 18 hours away from WhiteOak Creek. I’ll be making 2 stops each way to visit friends and family. It will be my first trip out west to shoot. Not sure how I’ll react to a hill.I was going to give you guys a bunch of good-natured shit about having to drive so far to shoot ELR, but then I realized that my last trip out to the desert was 6 hours each way
EDIT: And having lived in FL for 20 years, I know the mirage... I've got a video that's rendering now about the mirage on the desert trip. Insane
When are you heading up there?
I'm taking Rebecca out west in September.
And yes, I'll be bringing at least one rifle. If all I have for targets is cross canyon rocks, then we'll be shooting at rocks.
I think she'll love the whole trip.
I signed up for David Lyndsay’s ELR class. It’s the weekend of June 13.
We're doing a 7,000+ mile round trip. Starting SE of Tampa, hitting the Grand Canyon, Bryce Canyon, a visit with my oldest daughter at Hill, AFB.
From there, it'll be the Wind River range, Tetons, Jellystone, then anything else we have time for.
Probably hit the Bighorns and Badlands on the drive home.
I'm pretty sure we'll just take a couple of days to sit in the woods and enjoy some people free time.
Thanks. I’ve heard. Very excited to learn what it takes to compete under pressure.
Are you loading the 410’s ? I’m having difficulty with seating depth consistency using my AB dies. They work fine on CE400G2’s. I just ordered a bullet comparator set for bigger calibers. I’m gettin 0-.015” variations. Desired jump is .020” back.
I used my 12-year-old VIERSCO dies for mine and didn’t measure B-O on my loaded rounds.
I also did not measure B-O on individual bullets
I have the seating stem for my Warner tool company dies, but I find that I don’t use it very often because I don’t want to take the dye apart so I just use my old VIERSCO die
I also did not measure B-O on individual bullets
I have the seating stem for my Warner tool company dies, but I find that I don’t use it very often because I don’t want to take the dye apart so I just use my old VIERSCO die
It does.
It's also a good thing I really like my wife. 2-1/2 weeks together in the van could be a problem with a few couples that I know.
The 85# dog will be the interesting part. She's figured out the queen bed is really comfy...
Yeah, you definitely knocked it outta da park with your shooting cruiser. Still envious of it !
Having reservations with seating variations with my AB seating die/stem. I am experiencing a +\- ..020” window. No compacted loads. I’m using COAL as told. I just inspected the bullets and see score marks. The meplats also seem angled and a bit jagged. I’m prob over thinking this, but curious what the masses found.
I may get lucky and hitch a ride to the arena with Mike next week.
Looking forward to it, really like the range even though my elr shooting there sucks
And I agree, Mike and Rebecca did an awesome job with their vehicle!
I haven’t gotten any to try yet. Maybe this fall.
You can you the .375 insert for the Hornady shoulder bump gauge set as a bullet competitor for 375 stuff. I’ve done it that way for years.
If you’re seeing +/- .020” of overall length, that would seem a little high for me, but without seeing or measuring these bullets, it’s hard to tell. Jump is measured off the ogive, so I would just wait till I could measure that and go from there. Atips have a much more consistent oal than most other cup and core bullets.
So what COAL did you end up with at 25 back?
And how much of the bearing surface are you capturing in the neck ? I’m getting ready to load some test rounds 15 back that will have a COAL of 4.570” with approx half the neck support. Gonna check concentricity to make sure all is ok. May need to tighten neck tension.
my COAL is 4.340" and that has the shank/boat tail junction just at the neck/shoulder junction, by chance alone. and the Ogive is 0.025" from the lands. I have a carbide reamer, the exact one that DT uses which was designed around the CEB 352s, so that's why my throat is shorter that those with chambers designed around 450s or something like that.
I also shot some loaded 4.290 or 50 thou deeper, but only at range. My general intuition was that the velocity was not as consistent, so I'm going back to 4.340 or 0.025" off
I also shot some loaded 4.290 or 50 thou deeper, but only at range. My general intuition was that the velocity was not as consistent, so I'm going back to 4.340 or 0.025" off
Also, I did not clean out powder Valley. They still have them in stock for the same price I got them so go have it boys.
www.powdervalley.com
Berger Hybrid Target Bullets 375 Caliber (.375 Diameter) 410 Grain Jacketed Hollow Point
Berger Hybrid bullets are designed to achieve extreme accuracy for competitive and recreational target shooters. Berger Hybrid bullets combine a tangent ogive with a secant ogive to produce the highest possible with the least sensitivity to seating depth. This allows the reloader to take full...
www.powdervalley.com
There are endless versions of the loading process decision tree. Whether a particular process or strategy is a good idea or not depends on the other decisions you've made.
That being said, in general, positioning the back of the bearing surface ahead of the neck can be a good strategy. The back of the neck is stiffer because it's reinforced by the shoulder. The transition from the shoulder to the neck is a shit show after a few firings. This one is a 300 Lapua case that was turned after forming. It's been turned again after 3 firings using the same turning tool.
Using 0.006"+ neck clearance and positioning the rear of the bearing surface 1/4-1/3 of the way down a 1 caliber long neck will kick the need to turn down the road 10 or more firings.
If you don't neck turn, you'll likely see a benefit from moving the bullet down the neck. If you don't neck turn and have 0.004" or less of neck clearance because you don't want to "overwork" your brass, it's pretty much necessary to get consistent velocities.
I'm assuming we're single loading and not running them through a semi auto.
That being said, in general, positioning the back of the bearing surface ahead of the neck can be a good strategy. The back of the neck is stiffer because it's reinforced by the shoulder. The transition from the shoulder to the neck is a shit show after a few firings. This one is a 300 Lapua case that was turned after forming. It's been turned again after 3 firings using the same turning tool.
Using 0.006"+ neck clearance and positioning the rear of the bearing surface 1/4-1/3 of the way down a 1 caliber long neck will kick the need to turn down the road 10 or more firings.
If you don't neck turn, you'll likely see a benefit from moving the bullet down the neck. If you don't neck turn and have 0.004" or less of neck clearance because you don't want to "overwork" your brass, it's pretty much necessary to get consistent velocities.
I'm assuming we're single loading and not running them through a semi auto.
+- 0.020 on the length and you're worried about concentricity?
The variation in COA should be about the variation in bullet length. If there really is 0.040" variation in the length of those bullets, they need to be sorted to 0.005". Or trimmed. If you point them after trimming, leave a meplat that's 15-20% of the bullet diameter.
There shouldn't be a mark on the bullet from seating. Even good seating stems may need to be detailed. Blend away the transition to the contact area. Polish the contact area with fine lapping compound using a bullet in a cordless drill. Minimize seating pressure. I also use SOF2's Imperial Wax trick on the bullet and neck entrance. It lowers the seating pressure and makes inconsistencies in the neck prep more obvious. After seating, feel for jacket shavings when you remove the wax from the bullet. If there are any, upgrade your chamfer.
Thanks man. I’m probably in over my head here. Won’t be the first time. I don’t trim or point or sort. I don’t compete, but always strive for perfection. I think I’m gonna keep testing the 18 cases to see if I can achieve SX OF 5 or so and sub MOA. I had that with last batch at 100, but mile hit % was less than expected. Then I realized a mistake I made in chamber measurements(I have 2 CT’s) and bullets were like 145 back. Barrel is needing end of life and I’m really just checking these out. Thanks for your suggestions. I’ll get there.
Wow, very cool for you to share, and very informative. Looks like I will be looking into neck turning.There are endless versions of the loading process decision tree. Whether a particular process or strategy is a good idea or not depends on the other decisions you've made.
That being said, in general, positioning the back of the bearing surface ahead of the neck can be a good strategy. The back of the neck is stiffer because it's reinforced by the shoulder. The transition from the shoulder to the neck is a shit show after a few firings. This one is a 300 Lapua case that was turned after forming. It's been turned again after 3 firings using the same turning tool.
Using 0.006"+ neck clearance and positioning the rear of the bearing surface 1/4-1/3 of the way down a 1 caliber long neck will kick the need to turn down the road 10 or more firings.
If you don't neck turn, you'll likely see a benefit from moving the bullet down the neck. If you don't neck turn and have 0.004" or less of neck clearance because you don't want to "overwork" your brass, it's pretty much necessary to get consistent velocities.
I'm assuming we're single loading and not running them through a semi auto.
I did sort the 410's by length until I got 18 that were all between 2.055 and 2.060" to use for testing soon.
Out of the 30 or so I sorted, ES was 2.043 and 2.072". FWIW
At the range. Since I couldn’t find any load info for 410s with N570 in the 37XC, I extrapolated off my 390 ATip loads. I had been running 120 gr of N570, so decided to run the ladder from 114.5 to 119.5, with foulers at 116 and 117. Very low cell signal, so I can’t share pics, but holy crap these things perform.
Slightly heavy bolt lift at 117.5, definitive heavy lift at 118.5. Stopped there. My shoulder hurts.
Since there’s no load data for this combo, I’m going to start a new thread for the loads when I get home.
With random seating depth (.020”) I’m getting groups and SDs that I could almost run with.
Will post data later.
Slightly heavy bolt lift at 117.5, definitive heavy lift at 118.5. Stopped there. My shoulder hurts.
Since there’s no load data for this combo, I’m going to start a new thread for the loads when I get home.
With random seating depth (.020”) I’m getting groups and SDs that I could almost run with.
Will post data later.
Given his predisposition to use as much of the neck length as possible, if he has multiple firings on a brass/chamber combination that gives less than 0.004" of neck expansion after firing, it just may. It certainly has a better chance of clearing up the problem than working through tenth grain powder and 3 thou seating depth steps. Neck expansion is really fast to measure and everybody who reloads already has the tools. The post was intended more as a heads up about tight necks than a suggestion to neck turn.
Berger didn't create that bullet, Litz did. In 2014. Litz also suggests that if you're really serious, jacketed hollow points should at least be sorted on length as a proxy for meplat diameter to minimize BC variation. The caveat, and next big clue, is the correlation between length and BC variation in only ~50%. That tells us that there were other similarly sized effects in their tests. Could be measurement limitations, could be barrels, could be I just don't know what. Given the scatter in the match test data, I'm betting on barrels. I've had a 2300 yard range with a steep responsive backstop 30 minutes away for about 10 years. My own observations are as my barrels age, the BC trends downward a couple percent and the BC spread opens up about twice that. That happens before 100 yard groups and velocity spreads open up.
What AB labels as variation is 1 SD. In a 10 shot string, you'll probably see about 3X that. There is only a 50/50 chance that the best and worst in 20 shots will be in the same 10 shot string. 1 in 4 for 5 shot strings. I don't doubt that they have a 3% variation ATip CDM test on file, but doubt it's the norm. A 10 shot string would give something around 9% ES and that's really fucking obvious beyond a mile. I have copies of a few CDM data sheets forwarded to me with velocity ES under 10 fps and 4X the BC variation below 1%. All Lazers.
I took your group and velocities as "cross those off the list of things to worry about". Your house is in order. The 215M and H50bmg are soul mates, and not just with the 375CT and 400 grain bullets.
If groups are tracked electronically, it becomes obvious that they have Size averages and SDs similar to velocities. The SDs are more or less 1/4 the group size for 20 shot groups. 19/20 groups will be within 2 SD of the average. That gives groups from 50% to 150% of the average. Worst case scenario is your group was the best of 20 and the worst will be 3X it. Anything under a MOA works past 2000 yards, 3X your group size is still overkill. The group zeros float around about 1 SD so a half MOA average gives zeros within a click. I shoot 20 shots to the same aiming point. Sometimes as 5 shots, sometimes with 10. The ShotMarker gives the impact locations that are lost in the resulting hole. I turn 20 shots into 20 five shot groups. The last shots are wrapped around to include enough of the first shots to make 5. It should flag any organized temperature drift, but I haven't seen it yet.
I'm looking forward to hearing about your long range results.
Thanks for that. It's actually what I was fishing for.
In one of his books, Litz found the 30 cal 200 grain Hybrid BC changed about 1% per 0.010" difference in length.
I use that as an anchor point to scale the effect to different bullet weights and calibers. I might be off in my scaling factors, but the back of my napkin gives maybe 0.6% per 0.010" for the 410 grain 375.
It's not uncommon to find 0.030" difference in length in a box of 338 cal 300 grain hybrids.
I’m pretty sure the guy you are responding to hasn’t even fired any of these bullets yet but somebody correct me if I’m wrong
Y’all can sort bullets as much as you want, but I just loaded 20 of them and got the results you see posted above without any sorting or fucking around which is exactly what I was looking for and why I ordered over $1500 of them
If I had had to fuck around sorting them, I would’ve stuck with the 390ATIP
ETA: rocket man also posted above the he just went out and got positive results loading at the same distance off of the lands that I did but y’all haven’t even shot none of these bullets yet and you’re fucking around measuring everything
Just go shoot ‘em and see what happens.
Else you’re gonna sort them and trim your necks and do a bunch of other dumb shit and think that that’s what made positive results when all along You could’ve just loaded some and shot the fucking things and then be right where all the rest of us are but with a lot more trouble
FFS
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