The 22 creedmoor thread

[ACHILLES]

Sorry, I guess I was asking about pressure and trying to read primers. I wasn't very clear.

Primers are not always the best indicators of pressure in stout brass like Peterson. Also the 68gr hpbt will have more bearing surface than the 69eldvt and should pressure out with less powder. Another thing to consider Hornady load data is tested with Hornady brass which has slightly more capacity than Peterson. Generally to run the same bullet/powder at the same velocity I will have to run 1gr less in peterson brass than Hornady. Looking at your velocity’s alone you’re probably about as high as you'd want to go. Take your fired brass resize it and get a case head measurement just above the extractor cut. Work your way up measuring from the lowest to highest charged cases and write them down. You will notice most will be the same which should be the .470-.471 range depending on your chamber specs. Once you get around 47gr it may go up half a thou, to .4715-.472 showing you the pressure has increased significantly. It may not be those exact numbers depending on your chamber and calipers used. But start with the lower charges to find a base measurement then watch for the base measurement to grow as you get into the higher charges. If for some reason your base measurement hasn’t grown near the top. Load up 47.5 shoot, size, and measure. And if you want when you drop down and shoot to find accuracy. Once you’ve found it. Shoot and reload one case with that charge. If it’s toast and can’t be resized after 2-3firings your obviously running higher pressures.

 

[dårlig jeger]

Thank you all for the input. I am new to reloading and couldn't tell if I was missing something.

I will try the case measurements that @ACHILLES outlined above. That is a cool thing to learn.

I'm thinking I'll load up a bunch in the 45-grain range and see how they shoot.

 

[d9w834]

Sorry, I guess I was asking about pressure and trying to read primers. I wasn't very clear.

I plan to test more with 69gr ELD VTs and Superformance powder this weekend. I think there might be more room to go. If you look at the Hornady data, you'll notice the max load for 68gr bullets and 73-75gr bullets is the same which seems counterintuitive compared to every other powder listed.

My current hunting load is 77gr TMK, 45.2gr of Superformance out of a 20" barrel at 3400fps with single digit SDs and zero pressure signs.

 

[d9w834]

I plan to test more with 69gr ELD VTs and Superformance powder this weekend. I think there might be more room to go. If you look at the Hornady data, you'll notice the max load for 68gr bullets and 73-75gr bullets is the same which seems counterintuitive compared to every other powder listed.

My current hunting load is 77gr TMK, 45.2gr of Superformance out of a 20" barrel at 3400fps with single digit SDs and zero pressure signs.

Correction.. 46.2gr

 

[Pickettpuncher]

Need a little help. 18” preferred barrel. 7.5tw. I’ve tried everything. Barrel started out pretty slow but shot good. Now I’m getting some speed and can’t get a decent group. Usually end up with 1-2 flyers in each. Alpha brass, cci 450, 80eldm, h4350 and n560

 

[d9w834]

Need a little help. 18” preferred barrel. 7.5tw. I’ve tried everything. Barrel started out pretty slow but shot good. Now I’m getting some speed and can’t get a decent group. Usually end up with 1-2 flyers in each. Alpha brass, cci 450, 80eldm, h4350 and n560

I couldn't get any Hornady bullets to group very well... 75 and 80 grain eld-m and the 69 grain eld-vt. Tried the same powders plus a few others, only 3 or 4 nodes each, but results werent great on any of them.

Sierra 69 and 77 grain TMKs did well with pretty much any combination, and the 80.5 Berger with N560 shot one hole groups on both nodes tested.

I see a lot of people having success with Hornady bullets but I didnt want to waste any more barrel life trying to figure them out when the others performed so much better with no effort.

 

[swavescatter]

Go back down in speed or try another bullet. My barrel just didn’t want to shoot 88’s or either 80 ELD

 

[justin davis]

Need a little help. 18” preferred barrel. 7.5tw. I’ve tried everything. Barrel started out pretty slow but shot good. Now I’m getting some speed and can’t get a decent group. Usually end up with 1-2 flyers in each. Alpha brass, cci 450, 80eldm, h4350 and n560

Could be the bullet. I tried 75 eldms and was having similar. Some bullets grouped well but I’d get random flyers too

 

[mwoolsey5]

Sorry if I missed it already, jumping back in after a bit away from this thread, but for those having trouble with the heavier bullets, have you tried Varget?

 

[The Guide]

Need a little help. 18” preferred barrel. 7.5tw. I’ve tried everything. Barrel started out pretty slow but shot good. Now I’m getting some speed and can’t get a decent group. Usually end up with 1-2 flyers in each. Alpha brass, cci 450, 80eldm, h4350 and n560

Try the 80.5 Fullbore Berger. I've seen lots of variability in the lot to lot accuracy from Hornady 22 caliber bullets in both the 22CM and 22 ARC. Hopefully the 88 TMK won't be as finicky at speed when comparing it to the 88 ELDM.

Jay

 

[TradLife406]

Need a little help. 18” preferred barrel. 7.5tw. I’ve tried everything. Barrel started out pretty slow but shot good. Now I’m getting some speed and can’t get a decent group. Usually end up with 1-2 flyers in each. Alpha brass, cci 450, 80eldm, h4350 and n560

How many shots in your groups?
Next month the 88 tmks should be out.

I love the 77's. They shoot good.

For whatever reason like most guys my PVA barrel hates the Hornady. Which sucks because I can buy Hornady locally.

 

[mtnbound]

Need a little help. 18” preferred barrel. 7.5tw. I’ve tried everything. Barrel started out pretty slow but shot good. Now I’m getting some speed and can’t get a decent group. Usually end up with 1-2 flyers in each. Alpha brass, cci 450, 80eldm, h4350 and n560

Show some groups, how bad are the flyers? What's a decent group to you?

 

[mtnbound]

How many shots in your groups?
Next month the 88 tmks should be out.

I love the 77's. They shoot good.

For whatever reason like most guys my PVA barrel hates the Hornady. Which sucks because I can buy Hornady locally.

It will be interesting to see how the 88 TMKs fly. I just hope Sierra will up their production to match demand, the 107 6mm TMKs sold out pretty fast, and I assume the 88's will do the same.

 

[Pickettpuncher]

Show some groups, how bad are the flyers? What's a decent group to you?

Some of my first groups at 2900-3k fps Probably 5 shot groups


Groups from this week


I know I know, 10 shot groups are supreme, but if the first 5 won’t shoot the next 5 won’t either.

 

[huntnful]

Some of my first groups at 2900-3k fps Probably 5 shot groups View attachment 1027607View attachment 1027608


Groups from this weekView attachment 1027610View attachment 1027612


I know I know, 10 shot groups are supreme, but if the first 5 won’t shoot the next 5 won’t either.

Same bullet lot, same powder, same brass prep between groups? Virgin brass to once fired maybe?

If everything is exactly the same, and it’s just shooting bigger groups and faster speeds all of the sudden. Just clean the barrel.

 

[43.6N]

Where are you at in barrel life?
Action screws, bedding, scope bases and screws: all good here?
How are you sizing brass? Did something happen to your dies?
Muzzle crown? Suppressor? No damage or built up carbon?

 

[huntnful]

Where are you at in barrel life?
Action screws, bedding, scope bases and screws: all good here?
How are you sizing brass? Did something happen to your dies?
Muzzle crown? Suppressor? No damage or built up carbon?

Good call on checking screws. I check mine often so I always forget to mention that is definitely the first thing that needs to be checked when things go array.

 

[Pickettpuncher]

Same bullet lot, same powder, same brass prep between groups? Virgin brass to once fired maybe?

If everything is exactly the same, and it’s just shooting bigger groups and faster speeds all of the sudden. Just clean the barrel.

The brass is once fired. I’ve changed powder from 4350 to n560 because I wasn’t getting the speed. I got much better speed but I would get flyers with it. Barrel has about 180ish rounds thru it.