222 grouping photos - help me out please

[phillips321]

So guys,

 

When i first started reloading i figured out that 22.5grains of N133 being a 50grain VMax suited my 222. Well after a nice morning with VarmLR a few months back we talked about my reloading and how i could improve it. A few things were pointed out but my powder measurements weren't the best. As such i bought a Hornady Auto Charge (a bit fiddly to use but speeds up the process).

 

Well i decided to test the groups again now that I'm getting a little better at reloading.

 

I started at 22.2 grains and worked my way up to 22.7grains in 0.1 steps.

 

Here are the results:

<-- 22.5 <-- 22.3

<-- 22.7 <-- 22.6

<-- 22.4 <-- 22.2

I'd appreciate any advice on which group to go with. There was a fair bit of side wind today, and these are 5 shot groups, some shots i've cleared pulled so maybe count them out ;-)

Thanks in advance

[andybrock]

I'd do the whole lot again on a sill, no wind day!

[gbal]

Of the options-and 5 shots helps- I'd try some more 2.2/22.3.......and not the higher loads....

 

You might hope it's four decent shots and a wind caught one in the lower two loadings.

0-52g

Shoot on a wind free day when testing-wind can't be assessed out to 100y with confidence-you need to eliminate that variable-saves time and misery in the long run!

2x5 groups on a still day tell more than 10x3shots in wind...

 

I'd check too the powder measure for consistency-pour 22.3, then measure that same actual powder pour again...you should get 22.3 (+/_ .1 will do).Check a few this way,if you haven't done so already.

 

You might try small seating depth changes too-once an OK load is sorted.

 

.2/3/4 g more powder in the 222 will scarcely be noticeable in ballistic terms-the 222 is all about accuracy not another 50 fps velocity (it's a 250 yard cartridge-but a very nice one,capable of .3/.4 ctoc groups at 100y).N133 is good,50-52 g bullets usually best (slow twist).

If it's a bit windy,shoot fun reactive targets...enjoy,but it's not test data,just good rifle practice -though reassuring too-and it will get better,but pinging used 12 g cartridges end on-3/4 inch- isn't bad!)

 

gbal

[Andrew]

I'd do the whole lot again on a sill, no wind day!

Yes to that.~Andrew

[Swarovski1]

+ 1 to windless conditions.

[VarmLR]

+2 to the still conditions Matt. You can't really deduce too much if the wind is blowing a hoolie but you can probably get away with a few mph full wind. Gusty conditions = forget it.

 

 

I agree with gbal. The lower loads, particularly the 22.3 look good. There is a surprising inconsistency between 22.6 and 22.7 which aren't to do with a 0.1 grain load difference (I'd suggest) as that won't affect barrel time significantly. That's either trigger technique or the wind. It almost looks like you had a different grip on the rifle for the 22.6, or moved your cheek between rounds on that one which can introduce some parallax shift.

 

The other observation is that you have the lowest vertical spread at 22.2/22.3 which isn't wind-related. That can be an indication of low ES between rounds giving good consistent velocities but at 100 yds, you're unlikely to notice as much shift than at 200. For that reason, if you can, find a group that shoots in still conditions to at least 0.5moa (your rifle is well capable of that) and if you can repeat that at 200 (ie everything into an inch), that's more than good enough for your foxing.

 

If you want to know what the FPS average is, without using a chrony, you can estimate using the (preferably G7) BC, zero at 100, shoot a 5 or 6 shot group at 200 and measure the drop from your point of aim (ie do not correct for it). You have Strelock pro. Enter this drop into the drop calculator for MV and it will give you actual MV based on you bullet's BC. You can then develop a drop table. I'd suggest it will be iterative as G1 BCs are seldom accurate past 200 yds. Use the first 200 yd approximation and test again at 300. Take 300 yd drop using the calculated MV and re-calibrate bullet BC to 300 using this. That or buy a chrony!