Re: new Berger 338 cal 250 gr Hybrid - testers needed
OK, here we go.
I got my two boxes of the Berger Hybrid 250gr .338 bullets on 3/5.
I'm thankful for being chosen by Berger, I must say.
Some bullet data:
I figured that micing 50 out of the 100 bullets would be a valid statistical sample size out of a total of 100, so I only fiddled with one box.
Bullet lengths:
The Bergers, as others have noted, have random peaks, usually a single peak, above the meplat. This affects overall length.
Out of the 50 bullets that I measured, I had:
1 at 1.615"
2 at 1.619"
2 at 1.641"
The majority of the remaining bullets were clustered in the 1.625"-1.627" range, with a few below/above that range.
Bullet ogives:
Using my older Stoney Point comparator/bushing holder and a Hornady .338" comparator, I measured the ogives:
1 at .770"
3 at .771"
21 at .772"
23 at .773"
2 at .774"
Note, I didn't get any binding on the bottom of my SP holder, as it was deep enough to accomodate the slender noses of the Berger Hybrids.
Bullet weights:
RCBS CM 1500:
2 at 249.8 grs
15 at 249.9 grs
20 at 250.0 grs
10 at 250.1 grs
3 at 250.2 grs.
Testing enviroment:
I wasn't able to go to Manatee SE of Tampa, to shoot their 1000 yard range and the Palm Beach Sheriff's training facility range isn't going to do another 300 yard shoot until July, I think it is, so I'm stuck at 100 yards for this test. They did have the 300 yard shoot on 3/4/12, but that didn't help me out.
I last shot a rifle (at Manatee) on 4/8/11, when I shot my Savage LE2b and Sako TRG-42 at 1k. So it's been a good eleven months for me, behind any long gun.
Weapon:
I bought my TRG-42 in January of '06, so it's a 1:12" twist. I got the SB PMII 5-25x50 P4 scope and the 3 ring Sako 30* mount, along with the Sako bipod and muzzle brake.
I have 883 rounds down the barrel before this test. I've shot it about a half dozen times at 1k. I've also shot it out to 600 yards, at steel, a couple of times and finally, 300 yards prone, three times. Probalbly about 400-500 rounds between 300 yards and 1k. Not a lot, but there you have it.
After the last visit, I thoroughly cleaned the bore and left the turrets set for that distance.
Test subject:
You can see in my photos, the comparison between the 250gr Scenar, the Berger and the 250gr SMK here:
Let's get down to the nuts and bolts.
On 3/13/12, I was able to shoot my first small batch of the Bergers at 100 yards. I used the Sako bipod and a small rabbit eared sandbag under the butt.
Reloading details:
For the reloading particulars, I only had 24 fired Lapua cases, so since I didn't want to pull down any of my loaded rounds and since I didn't want to use new brass on this limited sample size of 250 Hybrids, I was in a quandry.
My go to load is between 88grs and 89grs of H-4831sc under the 250gr Scenars and 250gr SMKs. I'm stuck with the 250s due to my older 1:12" twist tube. I also load with VV-165 and VV170, as well as H-1000, but the Hodgdon powder works really well for a velocity of between 2875 and 2925 through my 27 and 1/8 inch barrel.
I figured I would go with 88.5grs of H-4831sc, since it is a known 'node' for me and fiddle with seating depth and let the cards fall where they fell.
Since I already had neck sized all of my cases, I couldn't use a dummy round per se, so to find the lands with this particular bullet, what I did was seat one long, color it with a Sharpie and chamber it carefully. Upon extraction, I'd look for rifling marks around the bullet's ogive, apart from the singular scrape in one area, you might find upon extraction.
Note, they were so long, I couldn't 'eject' a case, but had to remove the bolt to free them up!
I ballparked my lands at ~3.870"ish, so I backed down to ~3.848" for the longer batch, 3.823" for a shorter variation, then ~3.798" and finally mag length safe at 3.728". Remember, I have about 900 rounds down my barrel and I'm sure that there is a good .020"-.030" of throat errosion.
For hardware, I load on a 17 year old Dillon 550b. Charges were via the ChargeMaster 1500. Dies are a Reading Bushing neck die with a .365 TiNi bushing and a Forster Micro Seater die. The Forster's seating plug is way too wide for this sharp nosed bullet and the Bergers were easily seating off the bottom (top?) of the plug, with no side support whatsoever. This caused some slight deformation to the noses (peaks) of 'some' of the bullets, but not all. I'm sure runout was exacerbated.
The above is a caveat for shooting this bullet, as one will have to get an appropriate VLD plug to properly seat these bullets, even if they are just hybrids.
For the past seven cycles, I've noted that FL sizing actually increases my headspace by ~.005", so I've only been neck sizing my cases. They fit snugly in the chamber with a slight bit of resistance upon locking the bolt...no bother for me.
I loaded up only 20 Bergers and took an extra 15 rounds of 338LM that I already had loaded up with 250gr Scenars over 88grs of H-4831sc and 215Ms, to use as fouling/sighters. These were mag length at ~3.730". I used these as sight ins and foulers, since the bore was whistle clean.
The first picture is a detailed shot of the Bergers fired over two visits, 3/13 and 3/17. The second picture is of the entire target with the fouling/sight in rounds using the 250gr Scenar ammo.
Total rounds fired, was 59, since I lost a Lapua case a few cycles back in a terrifying kinetic bullet puller accident. The 338LM doesn't fit folks and I had to wrench it out, killing the case. We did have a nice funeral for it, however.
I wasn't able to chrono day 1's 20 rounds, but I did get my 17 yeard old Pact Model 1 to give me some readings on groups 2, 3, 4, 5, 6 and 7 for day 2, listed below.
First day I sighted in on the bottom left orange slice, 10 shots using the 250 Scenars. Low and right. I corrected a bit and fired the second group, which is bottom right and 5 shots.
For the Bergers, I started on the bottom row of black targets, second from the left--GP1, then when I knew that the POI wasn't some wild abberation, I moved to the left for GP2 and then three over to GP3 and finally GP4.
Day one, done. I did not clean the rifle at all.
Day two started with a fouled bore on the bottom row, on the far right...GP1 again.
These were loaded to a mag length (for me) of 3.728", for 9 shots (remember the dead case). The chrono wasn't reading until I removed the difusers, so no data on them.
I then moved up the right side, firing 5 shot groups, up to the top row and then right to left, on the top. The target gives you the particulars. The scope wasn't adjusted at all for the seond session.
As I got into the longer seated rounds, particularly on the 3.848" rounds, I noticed that they started shooting off the black and to the left. The wind was zero value and coming into my face, despite me writing "swirling" on the target. It was noticeable, but maybe 5 mph, so I don't think that had anything to do with it, as the flag on the 40' pole behind me was limp. at that time.
I had 1.25 MOA dialed in for LEFT, based on the first fouling group on the first day and had I backed that off, things would have been dandy, but that doesn't jive with the other groups which were shooting nuts on, so I don't know?
I can't explain why the earlier groups were pretty much on center with no wind deflection and the longer ones were off to the left under the same conditions.
I don't know if getting closer to the lands impacted the rounds and shifted them to the left, a bit, but it was odd.
Chrono data for the first 10 shots seated at 3.798" was 2860 fps with a few lower velocities bringing the SD up to 52.6. No bother, it's 100 yds.
Second two groups, I got 7 readings for an average of 2894 fps, for the seating at 3.823" and a SD of 21.1.
My 17 year old Model 1 needs a trip back to Pact for an overhaul, FWIW since it's been glitching randomly for me.
Finally, the last two 5 shot groups at 3.948" registered 7 out of 10 for an average velocity of 2889 fps and a SD of 22.1.
Epilogue:
We all know that just because a cartridge combo shoots MOA at 100 yards, doesn't mean it'll shoot MOA at 1000 yards.
However, if a cartridge combo can only muster 1.5 MOA at 100 yards, it'll never shoot MOA at 1000 yards.
These Berger 250gr Hybrids shoot really well out of my 1:12" Sako TRG-42 and while 100 yards isn't anything to throw a party over, they do shoot accurately at that distance and that's always a good start on the way to 1k, or a mile.
Thanks to Berger, once again.
Chris