• This Forum is for adults 18 years of age or over. By continuing to use this Forum you are confirming that you are 18 or older. No content shall be viewed by any person under 18 in California.

22 ARC Begins

Had to get on paper and shoot at 200 meters this morning. I forgot to check the calendar and see if the black powder guys were using the 100.

Screenshot_20240804_091138_Chrome_Original.jpeg

Have to say I was a little disappointed with the speed. Only 2590 fps with 28.0gn of H4350.

I will try N150 next.
 

Attachments

  • IMG_2840.jpeg
    IMG_2840.jpeg
    480.4 KB · Views: 34
I have an RTR 18" with about 700 rnds thru it, still just searching for results. My best load is 28.1 H4350 with Berger 85.5. Makes 2620 consistently. My main issue is the chamber is absolutely max length. I'm necking down Starline brass and using a false shoulder. I've exactly zero success with once fired brass. Everything measures fine, just won't group. But I'm not sure how much to expect from $300 barrel. ‍
 
Can we assume that you are seeing pressure at this speed?
Paul
Hodgdon shows a max charge of 28.0 gn at oal of 2.260” and pressure of 51,000 psi.

I am at oal of 2.295” (25 thou of of lands) but the cases are 0.030” shorter at the datum than fired cases.
The primers are flat but there aren’t any marks on the brass or cratering. I should be well below max right now.
 
View attachment 1578009

Picked up the barreled action today.
28” shillen 6.5 twist, straight, ec tuner, Curtis valor action, mpa matrix chassis with a march 4.5-28 fx/ tr1 reticle. Weights 23 pounds.

Loaded (25) rounds to zero and break in.
95gn SMK, 28.0gn H4350, Hornady brass, federal 205m primers. Hoping for 2800 fps.

Will post results tomorrow.
Very nice! I’m sure it will hammer!
 
I have an RTR 18" with about 700 rnds thru it, still just searching for results. My best load is 28.1 H4350 with Berger 85.5. Makes 2620 consistently. My main issue is the chamber is absolutely max length. I'm necking down Starline brass and using a false shoulder. I've exactly zero success with once fired brass. Everything measures fine, just won't group. But I'm not sure how much to expect from $300 barrel. ‍
My RTR seems to be doing great. What loads have you tried? I don’t think h4350 is fast enough. Have you tried anything other than the 85’s?
 
Had to get on paper and shoot at 200 meters this morning. I forgot to check the calendar and see if the black powder guys were using the 100.

View attachment 1578057

Have to say I was a little disappointed with the speed. Only 2590 fps with 28.0gn of H4350.

I will try N150 next.
I can get to speed I like in my 20” (28000-2850) with N140 and 80.5’s, but GRT says I’m about 4k over pressure (brass looks fine).

I have n540 coming today and plan to try this week.
 
I have an RTR 18" with about 700 rnds thru it, still just searching for results. My best load is 28.1 H4350 with Berger 85.5. Makes 2620 consistently. My main issue is the chamber is absolutely max length. I'm necking down Starline brass and using a false shoulder. I've exactly zero success with once fired brass. Everything measures fine, just won't group. But I'm not sure how much to expect from $300 barrel. ‍
On e fired brass seems to work fine for me, necked down Grendel brass is to think to close into my chamber. Loaded is like .253-2.54 compared to .249 factory arc brass. Fired brass is like .2545
 
My RTR seems to be doing great. What loads have you tried? I don’t think h4350 is fast enough. Have you tried anything other than the 85’s?
I've played with rl16, 6.5 SB, n540, cfe223, SB Match. I tend to want the most temp stable powder. My issue is the brass, I've been doing this for 40 years and never seen brass so all over the map after 1 firing.
I'm trying to locate some rl15.5. Also tried berger 80.5 FB, 80 vld's, I'm not to big on Hornady stuff.
It shoots great on new brass. ‍
 
I've played with rl16, 6.5 SB, n540, cfe223, SB Match. I tend to want the most temp stable powder. My issue is the brass, I've been doing this for 40 years and never seen brass so all over the map after 1 firing.
I'm trying to locate some rl15.5. Also tried berger 80.5 FB, 80 vld's, I'm not to big on Hornady stuff.
It shoots great on new brass. ‍
The RL15.5 seems to work well from what I’ve seen, Staball Match is ok but didn’t do much for me speed wise. CfE223 I traded for Tightgroup so …..
 
I’m using 29.5gns of 4350 in my 22 PPC to get 2880fps. I think you’ve got a lot of headroom to go faster.
I have (5) each of 28.5gn and 29.0gn loaded of H4350 to test next time.
Aren’t you shooting 90 gn SMK’s.
 
I have (5) each of 28.5gn and 29.0gn loaded of H4350 to test next time.
Aren’t you shooting 90 gn SMK’s.
I am. I missed that. My 22 BR barrels all maxed out about 1 grain lower: 32gn for 90SMK, 31gn for 95SMK. I need to check my notes but I was shooting the 95 at 2950 below max velocity and can push the 90 SMK up to just about 3100. All that to say you should see a lot more speed than you’re getting before maxing out. My first rounds down a new barrel are always disappointingly anemic, but speed comes right up as I work up the loads.

I’m excited to see where you get with it!
 
Update.

Fire formed (70) pieces of brass with Rl 15.5 and some 77gn rmr bullets that I had laying around. I didn’t load the bullets long enough and (5) rounds had light primer strikes that didn’t ignite the powder. Have about (100) rounds down the tube.

Fired (4) loads.

Screenshot_20240810_102155_Chrome_Original.jpeg

IMG_2936.jpeg

The 27.5gn of N150 was too hot so I stopped after the third case showed possible case head separation. Brass is Hornady 6 Arc fired (2) times then necked down to 22, fire formed to 22 Arc and reloaded once.
 
Last edited:
Update.

Fire formed (70) pieces of brass with Rl 15.5 and some 77gn rmr bullets that I had laying around. I didn’t load the bullets long enough and (5) rounds had light primer strikes that didn’t ignite the powder. Have about (100) rounds down the tube.

Fired (4) loads.

View attachment 1579824

View attachment 1579825

The 27.5gn of N150 was too hot so I stopped after the third case showed possible case head separation. Brass is Hornady 6 Arc fired (2) times then necked down to 22, fire formed to 22 Arc and reloaded once.
Thanks for sharing the info and data. More the merrier. That’s probably some of the best I have seen those RMR shoot too!
 
N540 testing.

It didn’t show much that makes me want to try the combo again, but the speed was nice. Once I find the depth the barrel likes with these 80.5’s, I may load up a high charge of the N540 and shoot a group, with a different primer too.


IMG_1409.jpeg
 

Upgrades & Donations

This Forum's expenses are primarily paid by member contributions. You can upgrade your Forum membership in seconds. Gold and Silver members get unlimited FREE classifieds for one year. Gold members can upload custom avatars.


Click Upgrade Membership Button ABOVE to get Gold or Silver Status.

You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.


To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.

Forum statistics

Threads
165,015
Messages
2,188,052
Members
78,639
Latest member
Coots
Back
Top