284 Thor Progress

[RH300UM]

I played hooky from work today. I loaded 33 rounds for my 284 Thor that Travis Redall built for me. With the ammo loaded as well as the truck I headed to the range 2 miles from my house.

Load info is as follows.Norma brass, Berger 180 vld hunting bullets,Fed. 215 Gold Metal primers. US 869 powder. I started the loads at 97.5 gr. and worked up in tenth incriments ending at 98 gr. I loaded 5 rounds for each weight Except the 98 grain load I only loaded 4 rounds due to fire formed brass I had avialable to load.

I cleaned the rifle barrel after every 2 shots as I am breaking in the barrel.

Results are as follows:
Group 1 1-3144, 2-3144?, 3-3180, 4-3187, 5-3154 avg.fps.3161.8 ES.43fps. Group size .558

Group 2 1-3154, 2-3190, 3-3167, 4-3163, 5-error avg. fps.3168.5 ES.36 fps. Group size .545

Group 3. 1-3161, 2-3189, 3-3165,4-3223,5-3208 avg.fps.3189.2 ES.62 fps. Group size .538.

Group 4. 1-3153, 2-3134,3-3158,4-3164,5-3170 avg.fps.3155.8 ES.36fps. Group size .550

Group 5. 1-3203,2-3186,3-3195,4-3177,5-3205 avg.fps.3193.2 ES.28 fps. Group size .520

Group 6. 1-3181,2-3253,3-3215,4-3248 avg.fps.3224.25 ES.72 fps. Group size .540

I went back to the loading bench and loaded 4 more rounds at 98gr. and raced back to the range trying to beat the snow that was headed my way.
The picture below is the result. I cleaned my rifle completely befor sending the last 4 rounds down range. Not cleaning every 2 shots this time.

Here is my surprise. The same powder load as the last group of shots in the previous session.

This group is as follows:1-3248,2-3253,3-3251,4-3242 avg.fps.3248. ES.11fps!! Group size .512!!!

The group sizes I know can be me. But the avg. fps. and the ES. are what have me somewhat puzzled.

Just the same I will continue with the 98gr. load and see if the results I got in the last shooting session today continue on.

Thought I would share this for those interested.

 

[blipelt]

One thing about mine, the groups weren't all that impressive at close range. With the low es. I seen some fantastic results at 300 to 600. I am betting you are going to be really happy when you go out farther.


Brent

 

[RH300UM]

One thing about mine, the groups weren't all that impressive at close range. With the low es. I seen some fantastic results at 300 to 600. I am betting you are going to be really happy when you go out farther.


Thanks blipelt your info was helpful to find a starting point for my load devolpment with this rifle.

 

[ICANHITHIMMAN]

May I ask your COAL for the round as it may be a suitable replacment for my HOWA when I'm finished with this barrel?

Jon

 

[RH300UM]

COAL is 3.420

Ogive is 2.718

 

[ICANHITHIMMAN]

COAL is 3.420

Ogive is 2.718

Thank you great post

 

[JARHEAD1371]

I'll pass on the advise Jim See gave me when I was developing my load. LEAVE THE CHRONY AT HOME!!! Shoot your groups at 300 yds and go from there. If you see a good one at 300, move out to 600+ and see how it does. When you find a load that groups consistently good at 800+ yds you will have a low ES. Then shoot over your chrony to see ABOUT what your velocity is, if you use a ballistic calculator for drops. That will get you close and you can use your actual drops to fine tune your velocity. After I did this I easily found a load that shoots 2.5" at 800 yds all day. I was just too concerned about the numbers the chrony spit out.

 

[RH300UM]

Jarhead1371, I somewhat agree with you. I can drive 5 minutes and shoot a 100yards and gather data or i can drive a hour each way,2 hours total, to shoot at our 1000 yard range.

At this stage I will chose the 5 minute drive due to time constraints and weather. I had a weather system blowing in. This happens alot this time of year. I can get more usable data at a 100 yards vs. 800yds. in 10 to 20 mph winds and snow.

 

[RH300UM]

Recieced 200 Wildcat 200gr. in the mail yesterday. I will load some soon (hopefully) and head to the range to see the results.

I will keep you all posted.

 

[GNERGY]

I wasted time shooting groups at 100 yds also cause most bullets don't stabilize until farther down range. I started shooting groups at 300 yds with a lot better results. Leave the chrono at home or just use it for velocity reference and don't worry about extreme spread. That is what I did with my 338 Ultra mag.

Tarey

 

[Oliveralan]

I totaly agree with going off real world 300 to 600yard groups rather than purely chrono data. Then chrono afterwards and more times than not ES will be low. I husky shoot ladder tests at 500. However here in VA for me this is pretty easy to do as I have my own range and it is cut out of the forest for the most part meaning there usually isn't any major wind to deal with like you guys out west often have. I often have all my flags showing less than 1mph "dial for" value total.

 

[NZ Longranger]

Sounds like you're on the right track with your loads. Our version of the 7mm/300 Norma we call the 7mm FatMax, as its the longest version of our 7mm Fatso's we can fit in a short action, all but a seriously lengthened one though. US 869 is the best powder we've found, and produces 3250 to 3300 fps with 98 to 100 grains with the 180 Berger VLD's and Hybrids at a measured 65,000 psi out of a 26" barrel. The tighter Lilja's etc are closer to 3250, while most other barrels will run 3300 fps. Our chambering has a BTO with the Hybrids of 2.790" for a 15 thou jump, or with the VLD's its a BTO of 2.785" for a 15 thou jam. Sounds like your throat and/or neck might be a bit shorter if you're 2.718" with the VLD's, depending on whether you're jumping or jamming?
Greg

 

[RH300UM]

I went to the loading bench this moring with the intent to load some 200gr. Wildcats. I hit a problem when I went to seat the bullet.

I have Neil Jones custom dies that were designed around the 180 Berger. Whan I seat a Wildcat the die makes a pressed ring on the ogive due to the shorter length from the metplat to the ogive on the Wildcat versus the Berger.

I have emailed Neil and I am waititng for a response. I am thinking he can make a new bullet seating stem to fit this different bullet.

Keep you posted on the results.

 

[Coyboy]

Just for clarification; how are you measuring your groups? .512" on the picture is a bit off, you need to measure center to center, or out side to out side and then subtract .284" from that.

On you ES and vel.

New barrels take some time to settle in. Typically they will increase in velocity over the first 40-80 rounds, depending some on the barrels manf. and cartige choice.

Also your ES should be a little high just from the fact of the constant cleaning you are doing to brake the barrel in, is changing with each shot the internal caracteristics of the bore.

My feeling is most guys would be best served to find a load that is a bit off of max and reasonably accurate. Either from past experience with a particular chambering and bullet, or from advice of a RELIABLE mentor. Load up 50-100 rounds and proceed to shoot them and shoot the barrel in. (also include whatever "brake-in" you believe in) At the end of 100 you should have a good stable velocity that has leveled off and is predictable. From there judge that loads accuracy, and tweak it for maximum performance in both accuracy and velocity.

Many times we mess with different loads too early in the barrels life. I have had loads that I developed in less than 20 rounds thru the gun. loaded up 100 of them and at the end of the 100 was showing pressure signs and velocitys over 80 fps faster than original development data.

My recent 6mmbr is a good example, first shots fired were 2825 ave. with 31 grains of varget. Now after 60 rounds 30.5 varget has them at 2852 ave.