clarification 7mmRm + ar2217 + hornady eldx 150g

Hey guys,

I have just made up several different loads forn my 7mm, and my 300 win mag.

I loaded up my 7mmRm first, as per the min and max powder amounts and loaded up 5 rounds of each going up .5g each lot of 5 rounds, after I made up 10x lots of 5 I went onto the 300winmag, 168g + 2217 again, although after loading the first few, I realised the casing was 85 -90% full before seating the projectile. After a quick bit of research, I realised that compressing the powder was normal but it made me think about the 7mmRm, and I knew the cashing were only 50% full, which meant no powder compression once seated.

So, I picked up a loaded round and shook it, I could hear the powder shaking around.... this is worrying me as I have made up 50 various rounds. Is this a problem? I stuck to the load data published by hornady, for the 150g eldx and the h1000 powder ( h1000 powder is equivalent to the ar2217 ).

Have I stuffed somthing up?

These are my first hand loads.....

Also is .5g a good amount to go up in weights by when developing a ladder load test? I also went to the maximum size - .20mm that the mag would allow for col.

Fire a few and find out.

.5gr increments is sensible

I would have thought your 7mm mag should be a lot more than 50% full with 2217. I use to use 71.5gr 2217 with a 162gr a-max. 300 win mag with a 168gr might need a faster powder than 2217.

If you are firing over a chronograph then 5 of each load at .5gr increments will waste a lot of rounds and give you a pretty sore shoulder.
With my 7mm mag I would load up 1 at each powder weight and fire over the chronograph. I would then start looking at the loads that gave the velocity I wanted and load 3 up at about 3 powder weights. Shoot those and go from there. Doing this I would usually get a 0.5-0.75 MOA load in about 20 rounds.

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Originally Posted by stug

I would have thought your 7mm mag should be a lot more than 50% full with 2217. I use to use 71.5gr 2217 with a 162gr a-max. 300 win mag with a 168gr might need a faster powder than 2217.

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How full was your 162g a-max? Mine was probably 1/2 to 2/3 full with the 150g eldx.

2217 was a recommendation to work for both rounds.

71 gn 2217 is >95% case capacity in 7mmRM. How much 2217 have you loaded in your 7mmRM Loads ??

61-67g of 2217,

Hornady shows that 61 -67g of h1000 which is an equivalent of 2217

Seems way too low for 150gn pills? For 162 AMAX like @stug says you’d expect to be running 71-72 gn 2217. So for 150gn rule of thumb says add 1gn powder for 10gns pill weight - so more like 72-73gn 2217 with a 150gn pill, but always work up from lower charge. I’d be starting at 69gn and working up, watching for pressure

Bugger messing round with loading up and testing that many rounds, just do a 10 shot ladder test and job done

I load 71 grs of AR 2217 with the 150 gr ELDX for 3071 fps COAL is 84.5 mm. These loads have a slight bit of space once the bullet is seated. You should always try and select a powder that will fill or near fill the case as this gives better ignition and burning which is desirable.

Hey guys
Just reading ur info about the 7mm Rem Mag
Hey im running 68 grains of 2217 , its doin 2700 muzzle velocity but is extremly accurate , question being should i be looking at trying to get this thing to be running faster or just leave it ? I do eventually want to shoot deer out to a K
Thoughts ????

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Sorry guys running the 162 A-max projies

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I have brought a buller puller and will pull these projecties and start at a higher amount of powder. So... a good range would be starting at around 68g of 2217, and go 69g, 70g, 70.5, 71g, 71.5g, 72g, 72.5g and 73g? Would 4x rounds of each be sufficient for a good group test ? or 3 or 5 ? With a bullet puller, Can I still use the projectile again ? or is it best not too? I will do some more of these developments next week when I am home so gettin all the information by then would be great.

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Originally Posted by Larskramer

I have brought a buller puller and will pull these projecties and start at a higher amount of powder. So... a good range would be starting at around 68g of 2217, and go 69g, 70g, 70.5, 71g, 71.5g, 72g, 72.5g and 73g? Would 4x rounds of each be sufficient for a good group test ? or 3 or 5 ? With a bullet puller, Can I still use the projectile again ? or is it best not too? I will do some more of these developments next week when I am home so gettin all the information by then would be great.

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I would not start that high. Its going to suck if you get to the range and find your start load is over pressure or close to, and you cant shoot any of the other 45rounds...

This is what I would do.
Load a ladder, one round of each, going up in .5gr increments from 64gr up to 72gr.
Start by shooting the 64gr cartridge and work your way up keeping an eye on pressure. Once you reach pressure signs you now know that your reloading efforts should be focused under that threshold.
Ideally you would also have a chrono, then during the initial pressure test you could look for flat spots in velocity and focus your loading efforts around those points.

If you must shoot some groups or test "accuracy" on your first outing/test, then I would highly suggest only taking multiples of lower powder charges. eg take like 5 x 64gr, 5 x 64.5gr, 5 x 65gr.... certainly don't take multiples from 69gr up to 73.... that's asking for a short day at the range. To be clear you are proposing to start at the book max and only work up higher from there. I understand others run slightly above book max, but that's not a starting point.
There are just as many people who cant reach book max without pressure, so there is a chance that ALL of your rounds will be un-shootable in your rifle which would make for a very inefficient load development process.

I would start at 64gr and go up from there.

Thanks Chris, So starting at the lower book limit would be good, but only go up 1 round of each until I see pressure signs, then back down to the previous load.
But from then, once I have found a good amount of powder - How do I go about working out somthing to give me better accuracy ?

The method of shooting a group with each powder charge and checking for groups is good. Just don't start that high because it will probably be time & effort wasted.

After determining the max powder charge that can be run before pressure signs, I would then drop back a few grains under that limit and begin loading multiples to test for grouping.
eg lets say we determined that the max powder charge in the particular rifle is 70gr. I would then load 5 rounds of each from 66 up to 70gr. 66, 66.5, 67, etc etc.

Lets just say that the 68gr was the most accurate out of those. Id then make up more variations around that mark but with smaller changes in powder charge. eg 67.8gr, 68gr, 68.2gr.
I would then pick the most accurate out of those, and if I was still not satisfied with grouping then I would make minor changes to the seating depth of the best shooting load.

If I was still not satisfied, Id change projectile. That is (one of) the processes to working up a very accurate load.

Quote:

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Originally Posted by ChrisW

The method of shooting a group with each powder charge and checking for groups is good. Just don't start that high because it will probably be time & effort wasted.

After determining the max powder charge that can be run before pressure signs, I would then drop back a few grains under that limit and begin loading multiples to test for grouping.
eg lets say we determined that the max powder charge in the particular rifle is 70gr. I would then load 5 rounds of each from 66 up to 70gr. 66, 66.5, 67, etc etc.

Lets just say that the 68gr was the most accurate out of those. Id then make up more variations around that mark but with smaller changes in powder charge. eg 67.8gr, 68gr, 68.2gr.
I would then pick the most accurate out of those, and if I was still not satisfied with grouping then I would make minor changes to the seating depth of the best shooting load.

If I was still not satisfied, Id change projectile. That is (one of) the processes to working up a very accurate load.

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absolutly perfect! thanks chris.

I have a "range" i can test locally, but not in a controlled enviroment with seating etc. So the initial pressure test will be fine to do there.

once i have pulled the projectiles off those rounds, Can I reuse the projectiles? or are they now buggered? Also - I have had to order a new collet for the eldx range as a few of the 300wm rounds had a crease put around the ogive of the projectiles upon seating, again.. wil these be stuffed once they have this crease ?

You can still use the pulled projectiles. If you are using a collet type puller just don't clamp down on them too hard.

Maybe post a picture of the .300 projectiles, Id think they would be ok and the only detriment might be slightly reduced accuracy, but without seeing the damage its hard to really say.
I would generally use such damaged projectiles for fouling shots, sighters, even the pressure test as accuracy is of no concern; and use only non-damaged ones for the serious accuracy/group testing.

Quote:

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Originally Posted by ChrisW

You can still use the pulled projectiles. If you are using a collet type puller just don't clamp down on them too hard.

Maybe post a picture of the .300 projectiles, Id think they would be ok and the only detriment might be slightly reduced accuracy, but without seeing the damage its hard to really say.
I would generally use such damaged projectiles for fouling shots, sighters, even the pressure test as accuracy is of no concern; and use only non-damaged ones for the serious accuracy/group testing.

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perfect, what a massive help. I have a Lyman magnum bullet puller on its way.
I have made myself a little bit of a plan if you wouldnt mind looking over it quickly? Also Are these powders ok for both of these ? Or would you or somone else recommend a different powder? From what i can tell 2217 is good for 7mmRm, and ok for the 300.

7mmRm
1x 150g hornady eldx + 64g ( min book amount )
1x 150g hornady eldx + 64.5g
1x 150g hornady eldx +65g
1x 150g hornady eldx +65.5g
1x 150g hornady eldx +66g
1x 150g hornady eldx +66.5g
1x 150g hornady eldx +67g
1x 150g hornady eldx +67.5g
1x 150g hornady eldx +68g
1x 150g hornady eldx +68.5g
1x 150g hornady eldx +69g
1x 150g hornady eldx +69.5g
1x 150g hornady eldx +70g
1x 150g hornady eldx +70.5g
1x 150g hornady eldx +71g
1x 150g hornady eldx +71.5g
1x 150g hornady eldx +72g ( max book amount )
1x 150g hornady eldx +72.5
1x 150g hornady eldx +73g


300WM
1x 178g hornady eldx + 76g ( min book amount )
1x 178g hornady eldx + 76.5g
1x 178g hornady eldx + 77g
1x 178g hornady eldx + 77.5g
1x 178g hornady eldx + 78g
1x 178g hornady eldx + 78.5g
1x 178g hornady eldx + 79g
1x 178g hornady eldx + 79.5g
1x 178g hornady eldx + 80g
1x 178g hornady eldx + 80.5g
1x 178g hornady eldx + 81g
1x 178g hornady eldx + 81.5g
1x 178g hornady eldx + 82g
1x 178g hornady eldx + 82.5g
1x 178g hornady eldx + 83g ( max book amount )
1x 178g hornady eldx + 83.5g
1x 178g hornady eldx + 84g


And fire each round, Over the Chrono , record the speed aswell as look for pressure signs. Then once pressure signs are apparent, Drop back to the previous load.

Next step : Once I have figured out the correct pressure range for my setup eg.70g for the 150g 7mmRm, then load 5 of each of 67g, 67.5g, 68gm 68.5g, 69g, 69.5g, 70g.

Next Step : Once fired, Choose the recipe with the best grouping , eg. 68.5g , and load up 3x rounds of 68.1g, 68.3g, 68.4g, 68.5g, 68.7g, 68.8g ?

If im still not getting any good accuracy then I need to switch projectiles or powder ?

"Next Step : Once fired, Choose the recipe with the best grouping , eg. 68.5g , and load up 3x rounds of 68.1g, 68.3g, 68.4g, 68.5g, 68.7g, 68.8g ?"

Yes you could load 5 of each of those powder charges (or however many you want) if you wanted to be thorough about it. I think when you start getting into .1 and .2gr increments (on a large capacity case like a magnum) its time to move to seating depth tests as we are looking "resistant" loads with a big velocity flat spot where .1 or even .2gr shouldn't make any meaningful difference. More on that below.

In regards to shooting the pressure test over the chrono - if you can do that it gives you a much more accurate starting point for your development.
If you can identify flat spots in velocity, where additions of powder result in minimal changes in velocity - then those are the places to start your load development around.

I previously described doing it without the chrono, but with a chorno instead of doing a run from (example) 64gr up to 70gr then picking the best and going from there, I would only make loads around the areas where there were minimal changes in velocity.
Ideally you want to focus your efforts around areas where velocity remains stable over a fairly wide powder change. This makes for a very resistant load. ie if you got a bit sloppy with your powder charges or your scale deviates by a little bit, it wont really make a difference as you are looking to work within a wide "node"

See this thread in particular my post where I did a pressure test as I describe, and identified flat spots in velocity in which to focus my future development. Note that for example from 69 to 70gr velocity only changed by 21fps across a whole grains addition of powder, and by comparison to other places in the test this is a definite flat spot...that means in theory as long as im anywhere in between those charge weights, velocity should be consistent and so this should make for a very resistant load.

https://www.nzhuntingandshooting.co....55/index3.html

In cartridges of .30-06 or 7mm mag size I would only load in 1 grain increments for your ladder test. Look for the cluster of 2 or more shots from successive loads and then work on the variables of seating depth and possibly fine tuning the powder charge. 5 or 6 rounds max should do the job.

Anecdotal data and manuals will tell you about where you want to be with a given powder and projectile. But you need to work up to this with your ladder test to be safe first off and confirm the load velocity and accuracy node is the same for your rifle.