338 Lapua/Berger 300 OTM/RL33

[D.Stone]

Initial Velocity Test.

Rifle: Accuracy International.
Barrel: Proof Stainless Steel.
Twist: 1:9.4
Length: 26 inches.
Chamber Notes: Berger 300 OTM will touch the lands at 3.810 OAL. It's jumping around 20 to 30 thousandths when loaded to magazine length.

Cartridge Data: 338 Lapua Magnum
Brass: Peterson
Powder: Reloader 33
Bullet: Berger 300 OTM
Overall Length: 2.980 base to tip
Primer: CCI #250 LRM

Atmospherics
Temperature: 68 F
Station Pressure: 29.30 hg
Density Alt: 1300 ft
Humidity: 32%

Other Notes:

This is with brand new Peterson brass. Brass is ran partially into an RCBS FL Sizing die to make sure the necks are round. Powder is weighed out on a laboratory grade scale to less than .1 grains.

The barrel is also brand new with 0 rounds fired.

I also had issues with the chronograph not picking up some shots, so that is going to be annotated in the notes.

94.0 gr
Velocity: 2590 fps
SD: 10.9 fps (5 rounds)

95.0 gr
Velocity: 2612 fps
SD: 13 fps

96.0 gr
Velocity: 2658 fps/ 2695 fps *
SD: 18.8 fps / 6 fps
ES: 34 fps / 14 fps

97.0 gr
Velocity: 2687 fps
SD: (Was only able to get 2 rounds to chronograph.)

98.0 gr
Velocity: 2758 fps
SD: 13.6 fps
ES: 34 fps

* The second number are the last 5 shots of the day. I wanted to see if the barrel was speeding up as it was broken in, and there was a very noticeable improvement in precision towards the end. That might be because the shooter just decided to shoot better, or the barrel/throat is setting in.

Range Note: A lot of these numbers are not going to be perfectly reliable due to the mounting bracket of the Magnetospeed coming loose. We didn't find the proper allen wrench until the end of the day. When we revisited the 96.0 gr load, it showed a lot more consistent numbers.

Final Notes:

None of the rounds show any signs of being over-pressure. Further research last night lead me to believe that up to 102 grains of Reloader 33 is "safe" (well the gun and brass won't explode...but it might be over-pressure.)

The next step is to work up even higher. I am hoping that we can achieve good results around that 99 gr - 101 gr mark with a velocity of around 2850 fps.

Based on the feeling of seating the bullets, I believe the consistency of the ammo will be improved by the use of an inside neck mandrel from Sinclair to have more consistent neck tension. The seating depth will also be reduced by 5 to 10 thousandths because some rounds were getting caught up in the magazine.

 

[centerlineseal]

So far, ... consistent with my results in a TRG42. My best node is at 97.0 to 97.5 gr RL33. Keep up on the report. It's appreciated.

 

[D.Stone]

Initial Velocity Test

Previously, I had ended on 98 grains of powder without any pressure signs. We had a lot less problems with the way the chronograph was mounted, and was able to get more solid data than before.

99.0 Grains
Velocity: 2770 fps
SD: 10.8 fps
ES: 26 fps

100.0 Grains
Velocity: 2813 fps
SD: 12.4 fps
ES: 28

101.0 Grains
Velocity: 2855 fps
SD: 11.3 fps
ES: 29 fps

102.0 Grains
Velocity: 2901 fps
SD: 16 fps
ES: 34 fps

Range Notes:

The weather was very similar. I have the atmospheric data written down in a notebook that is not currently with me. All of the loads show similar ES numbers over a 5 round sample size. The 102 grain load showed a higher SD, but also a noticeable higher point of impact on the target. My gut feeling is that the 99-102 grain range will shoot very well, and the 96-97 grain range is another good area to explore.

I will put up some pictures from my phone. The groups were not that great...with the smallest one being right around 3/4 MOA. There is definitely some trigger-jerker error in there for sure.

My gunsmith suggested that I should take the barrel off and make sure the receiver face is clean and dry by hitting it with break cleaner, and actually torquing the barrel on with a wrench before tightening the quick-lock system. I am sure glad that I did tear down the rifle completely...because the face of the receiver was absolutely coated in some kind of oil. I don't know if it's because the previous owner had done so, or if it came from the factory that way.

Anyways, the rifle is back together with a clean receiver face, and I have 30 rounds of ammo that is loaded up to test at distance sometime this week. We will definitely see if the AI Quick Lock actually returns to zero when the barrel is removed and replaced.

 

[D.Stone]

Here are some pictures. Enjoy.

 

[Zero333]

I found RL-33 gives a velocity and Point of impact plateau when in the node area.

That's not the case with all powders, but RL-33 was very obvious at 200 meter load development. Probably harder to see it at 100.

When you find a node that's consistent 3/4 moa (or better), just call it good and have fun lobbying them at distance.

 

[D.Stone]

I found RL-33 gives a velocity and Point of impact plateau when in the node area.

That's not the case with all powders, but RL-33 was very obvious at 200 meter load development. Probably harder to see it at 100.

When you find a node that's consistent 3/4 moa (or better), just call it good and have fun lobbying them at distance.

I'm expecting huge improvements from the trigger-yanker just getting more used to the rifle. That, and I feel a little better about how the barrel is attached to the gun.

 

[WAMBO]

Sweet setup,when I tested RL33 in my Lapua I started at 93grs and went up to 103grs.
The 93gr load shot one of the smallest groups I ever shot at 300yds, 1/2" for 3 shots but the velocity was very low, topping out at 103 gave me 2935 fps out of a 30" barrel with a 3 shot 1.5" group at 300yds, 102grs shot best at 1K at 9.75" for 5 shots.

 

[hambone1971]

Sweet setup,when I tested RL33 in my Lapua I started at 93grs and went up to 103grs.
The 93gr load shot one of the smallest groups I ever shot at 300yds, 1/2" for 3 shots but the velocity was very low, topping out at 103 gave me 2935 fps out of a 30" barrel with a 3 shot 1.5" group at 300yds, 102grs shot best at 1K at 9.75" for 5 shots.

What bullet you using in this test? Just curious. Thanks HB

 

[WAMBO]

Ah yes, I should have mentioned that, Berger 300 gr OTM.

 

[davidjoe]

Stone, try the Capstone sister bullet. 97-99 grains of Re 33. I’m unable to explain why but not whether, just shoot the Lapua 300 and then please keep the thread updated.

 

[D.Stone]

Short post.

I took the 101gr load out to distance this week. Managed to get out to 1500m.

I also did a paper test at 495 meters to see what vertical dispersion was. Vertical measures around 1.5 inches. The data across the chronograph said that the SD was around 16 fps and the ES was 47 fps. I think that might be the chronograph getting buffeted by the muzzle brake and settling in a slightly different orientation...but I have no idea.

The AI AXMC barrel returned to zero on the first shot, which was impressive. I only fired one shot at 100m to confirm zero.

 

[Ol’ Ed]

Here are some pictures. Enjoy.

Hey D.Stone, I like the way you’ve rigged your magnetospeed. That’s a great idea! What brand of bipod is that? Thanks!

 

[D.Stone]

Hey D.Stone, I like the way you’ve rigged your magnetospeed. That’s a great idea! What brand of bipod is that? Thanks!

The bipod is a Phoenix Tactical bipod from a company that is located in the United Kingdom. I was borrowing it, so I don't have any strong opinions on it.

 

[Ol’ Ed]

Ok, thanks.

 

[D.Stone]

I've shot around 150 rounds of the 101gr loading. It seems to be pretty decent out to 1650 yards. I am shooting across the saddle of a mountain, and I think we get quite a bit of vertical wind compared to what I am used to.

 

[D.Stone]

If anyone wanted some data on how temperature sensitive RL33, I have some data.

Well the good news is that it still works when it's cold out. The second shot was an outlier at 2900fps.

Comes summertime, I am going to go further down the rabbit hole and figure out exactly what I need to do to cut my standard deviation down. It's acceptable for plinking, but not what I want.

My summertime velocity was 2860fps. My winter time velocity is 2870fps. I haven't done enough testing to come to a permanent conclusion, but I am leaning towards RL33 not being temperature sensitive.

One of three things probably happened.

1. Reloader 33 is not temperature sensitive, even though it isn't marketed as such.

2. Reloader 33 is temperature sensitive but it has been masked by a new barrel that has gotten faster as it's worn in. I might find out that my new summertime velocity is around 2900fps.

3. I need to repeat the test after leaving the ammo outside for more than 24 hours, and that may change the result. The initial test was ammo that went from the backseat of my truck cab to the rifle. It may have warmed up.

I left 5 rounds outside in the snow for about 30 minutes with the intention of chronographing them, but I was only able to get one shot to register before the Labradar shutoff due to the cold. That round registered at 2870fps.

 

[cuznguido]

Have you tried RL22 and/or H1000 as a comparison with the RL33?

 

[D.Stone]

Have you tried RL22 and/or H1000 as a comparison with the RL33?

I have not.

RL22 and H1000 are probably a better fit for the 250gr range of bullets.

The other powder I would try with this bullet is N570...but good luck finding that in stock anywhere.

 

[cuznguido]

Actually if one is going to wish, he should wish for some H870 , but the reason I asked the question, I have never tried the RL33 but will do so soon after seeing your results. I have always preferred H1000 to everything else I have tried, with RL22 acceptable but not great. But I was fortunate enough to acquire some N570 recently which will be my next experiment.

 

[bozo699]

Has any of you tried us869 in your .338Lapuas?
Wayne