Long range load development at 100 yards.

[Erik Cortina]

Jenius, load 39.5, you should be ok.

 

[Link]

Erik could you take a look at my post please ?

http://forum.accurateshooter.com/index.php?topic=3819324.0


thanks

 

[southtxhunter]

41.5 isn't in the pic but it helped picking out 41. Forgot to load 40 so it's not in the 1st pic but in the second pic.

southtxhunter: Where did you come up with 41gr was your node? Just curious. To me it appears your node is either 40.0 gr or 40.5 gr area. As 39 and 39.5 and 40.5 hit very similar vertically. I can't tell because 41 appears to be shot at a different part of the target but it appears it hits almost same vertically too. Where is 40.0 group?

I would drop down to 40.0 and shoot for seating depth and I think you would be in the middle of a pretty large node?

 

[dieselten]

Here is another test with my Accuracy International 6.5 x 47L with Sierra 142's and H4350 from 38 to 41 grains, the top row was some other loads. I potentially see 2 nodes, one between 38.5 39.0 and another between 39.5 to 40.0. What do you guys think? I tried loading 41.5 but I couldn't seat the bullet, there was too much powder in the case. No pressure signs at 41.0.

Thanks

So everyone can see the final results, I loaded up a bunch of rounds with 39.8 H4350 at -.025. The center shows the progression from Clean Cold Bore to a settled condition with 5 shots. The upper right shows 5 shots with the Magnetospeed bayonet attached - 2727 FPS SD-7, notice the difference in elevation with the Magnetospeed attached, this is consistent with all of my previous tests. The bottom left is 10 shots at 100 yards. Thank you Erik for identifying this procedure!

 

[Erik Cortina]

Nice shooting dieselten. What do your chronograph numbers look like?

 

[dieselten]

5 shots:
2717
2726
2729
2726
2738

2727 average
7 SD

These were the 5 shots at the upper right red diamond

 

[savageshooter86]

that gun will shoot

 

[barnesuser28]

Tested my 284 win yesterday with the 52.8 grain charge you guys suggested. Here are the targets. There was a 1/2 MOA adjustment right after the .058" off group.

 

[barnesuser28]

I want to load up 5 rounds to shoot at 300 yards to check for groups, what load should i choose? I am thinking .07" off.

 

[mac86951]

Well, what is interesting is that the groups opened up then tightened again. What happens at 0.050-0.056" off, as well as 0.070-0.076? I think what you found was what we'd call an anti-node, and its worth doing a little
more to see what happens around those ranges.

 

[barnesuser28]

Well, what is interesting is that the groups opened up then tightened again. What happens at 0.050-0.056" off, as well as 0.070-0.076? I think what you found was what we'd call an anti-node, and its worth doing a little
more to see what happens around those ranges.

My gun does not like these bullets any closer than .045 from the lands, like it shoots 1.5-2 MOA. I will see if i am able to seat out to .076" off without hitting the donut, i think i am though.

 

[Ed333]

Related question for Erik and other knowledgeable posters, in the context of this thread, what chronograph would you recommend for a nice balance of price and value? Not looking to spend a whole lot if not necessary. I have read some good things about magneto barrel mounted units...???...easy to use?

 

[savageshooter86]

if you know how to place a strap on your barrel then you are gtg using the MagnetoSpeed. Search the threads for this. There are a TON of threads. It is easy and you can't shoot the thing!!!!!

 

[Erik Cortina]

if you know how to place a strap on your barrel then you are gtg using the MagnetoSpeed. Search the threads for this. There are a TON of threads. It is easy and you can't shoot the thing!!!!!

Do not hang something on the end of your barrel to work up loads and then take it off after load development, not a good idea.

I use an Oehler 35

 

[Ed333]

if you know how to place a strap on your barrel then you are gtg using the MagnetoSpeed. Search the threads for this. There are a TON of threads. It is easy and you can't shoot the thing!!!!!

Do not hang something on the end of your barrel to work up loads and then take it off after load development, not a good idea.

...

But if I am shooting a Savage Model 12 F class, in 6 BR, with a one inch barrel, off a Sinclair competition rest, is it really going to make that much of a difference in velocity or accuracy? Or is it analagous to 'tuning' with a barrel weight, and then undoing it, maybe getting a false reading?

 

[Erik Cortina]

if you know how to place a strap on your barrel then you are gtg using the MagnetoSpeed. Search the threads for this. There are a TON of threads. It is easy and you can't shoot the thing!!!!!

Do not hang something on the end of your barrel to work up loads and then take it off after load development, not a good idea.

...

But if I am shooting a Savage Model 12 F class, in 6 BR, with a one inch barrel, off a Sinclair competition rest, is it really going to make that much of a difference in velocity or accuracy?

Yes. Read about how a barrel tuner works.

 

[Nomad47]

My MagnetoSpeed bayo is attached for ALL my shooting. But I also don't compete except for an informal long range steel competition.
If I did shoot F Open, I likely wouldn't work up the load or compete with the bayo attached as it is impossible to attach it in EXACTLY the same position every time. But for my type of shooting, it is fantastic. I have a record of every shot fired and can monitor how changes in temperature, humidity, altitude, etc affect velocity. It has also been instrumental in determining when a carbon ring needs to be removed.

 

[BoydAllen]

How so?

 

[Nomad47]

The carbon ring? When velocity starts to rise, I check CBTO to lands. The measurement indicates the throat has shortened (which is impossible). I then spin a bronze brush (larger than caliber) in the chamber neck area, then recheck CBTO to lands. The measurement is back to normal and so is my velocity.
Hope that made sense.

 

[BoydAllen]

I am glad to hear that you have a method to monitor the problem, and a way to fix it. There is a matter of definition that relates to this that I will mention. Those that have experience with what they refer to as a carbon ring, will tell you that it cannot be touched by spinning a bronze brush, and according to their definition of the term, what you have is a buildup of powder fouling at the end of the neck part of the chamber. I am not quarreling with what you are doing at all. It seems to me that you have the entire situation under control, except that in that situation, I might be spinning the brush every time that I cleaned. The kind of carbon that they and I am referring to, has been compressed by the passage of bullets and by that, hardened to the point that the only way to remove it is by the use of an abrasive. Thankfully not all powders seem to have this characteristic.