Reply with quote #9
I am waiting for a barrel to do a 22 x 47L myself.
This one will be a fast twist number as well.
If I could get 3500 FPS with 80's I'd be more than happy.
Reply with quote #10
I've read that there are some people able to get 3400 using a 22 Dasher....I'm thinking the 6.5x47 Lapua cases should be as strong as the Lapua BR cases. With their greater capacity, 3500+ should be doable with an 8 twist barrel and an 80grn bullet....for sure with the 75 Amax's and a 9 twist.
If not the simple necked down version, then surely the AI version would....at least I hope. I have some brass coming in order to get mesurements for a possible reamer build shortly. I've been looking at diagrams of 22-250AI as compared to the 6.5x47L and they are comparible...with the edge going to the 22-250AI. But if the Lapua was also AI'ed it would give more capacity then the 22-250AI......and we know how the 22-250AI can perform. In theory, the Lapua should be the better round anyway. Someone will have to build one to find out for sure though.
Maybe me, if I can't shake this bug!!!
Reply with quote #11
Couldn't resist...so I built one.
Gt the brass in and started doing some measuring and found the measurments very close to a reamer that I already have on hand...the 22-6mmAI. Only had to hold it out far enough to ream all the chamber out of a 9" twist Savage 223 Varmint barrel I had laying around.
So, with nothing to do today, I did the chamber job, mounted the barrelthen sized the brass so that I created a slight false shoulder using a 22BR die, then fire formed 10 of the cases. Was in the process of getting setup to chrony a few when it started raining.... ...now I'll have to wait until tomorrow to get some loading work done.
I'll keep y'all posted.....
Reply with quote #12
Finished fireforming 30 cases this evening and shot for groups while I was at it......I was impressed with the groups. With no work other than loading and shooting, I was getting consistant 1/2" groups.
Velocity was unimpressive though.....3200FPS average using IMR 4831 and 64grn WW elcheapo bullets. Have not tried to work up any loads yet...just forming brass and checking groups while doing it.
I think this is going to be good shooter. Using those cheap bullets and just picking something from the 22-250AI loading data I have, it shot very well with no other work. Now that the brass is formed, I'll start seeing what it'll do for speed and accuracy using Sierra 65grn SPBT's; Sierra 69 BTHP's; 75 & 80grn Amax's.
Reply with quote #13
Didn't go huntin this morning so started working on a new load.
69grn BTHP Sierra, 38grns IMR 4350, 3423FPS average
This is going to be close to max....the primers are just starting to show a little pressure. Hope to find max load tomorrow. Maybe I'll be able to break 3500...
Reply with quote #14
I understand that Forster is making dies for this now and the 6mm version. I will email them later for the specs.
Reply with quote #15
Hi Guys: Delville & Jim
Sorry to be so lax about getting back to you. Re: .2247L
Let me digress here for a moment. I have a .22 Dasher That like James Phillips ( Guns of the week #30 ) will shoot 80 grain Hornady A-Max’s under 2” at 600 yards. It shoots better than any gun I’ve ever owned. I’m shooting them at 3330 fps. But I felt a need for speed and I would like to shoot the 90 grain Berger VLD’s. The Br. Case just did not have the capacity to drive a 90 grain bullet at the speeds that I wanted to work in.
I ordered a .22 x 47 Lapua reamer from Dave Kiff at Pacific Tool. I again wanted a no turn reamer and asked him to make it with a .253” neck
So I get another Wichita action and build a Identical mate to my .22 Dasher, only in .2247L. I have never used 90 grain .22 before. I observed a few posts that said if you wanted to use 90 grain vld’s you would need a 1 in 6.5 or a 1 in 7” twist to stabilize them. So I ordered a 30” Broughton 5C in .22 with a 1 in 7 twist.
I later learned that the posts regarding the fast twists were to be applied to the, 223/90 grain combo. In the .223 case, due to the slow speed of the bullet 2750 fps. A higher rpm is needed to stabilize the heavy bullet. ( 282,857 rpm’s )
It is amazing how good the 90 grain Burger VLD bullets shoot at 600 yards, that is if you can get them to 600 yards. My starting load was at 3400 fps.( 349,000 rpm )
In a string of 10, I may have only blown one up. But the next string of 10 only 4 may have made it to 600 yards. I then slowed them down to 3300 fps, (339,428 rpm) still losing bullets. So down to 3250, nope, now to 3200. Things are looking up I’m only losing 1 of 10. Now down to 3150 Ah ‘, success. All bullets arrive at 600 yards.
But I’m now at 3150 fps (318,857 rpm ) still to many rpm’s to be reliable and I would like 3400 fps. The barrel now has about 300 rounds thru it. Remember it’s a 1 in 7”.
Order new 31” barrel with a 1 in 8 twist.
New ball game. 80 grain Hornady A-Max’s happy at 3600 in the cool of the morning. I shoot in So. Ca. at approx. sea level, Maybe 500 ft’ elevation. Two weeks ago I tried this load in a Varmint silhouette match. I started at crows @ 300 yards 9:30 a.m. 68˚ got all 10. Next were squirrels at 400 yards approx. 10:15 a.m. 76˚ got all 10. Now to rabbits at 500 yards. Approx.11:00 a.m. 82˚ missed one ( me-hua ) also blew-up one bullet. At Prairie dogs at 600 yards I missed two ( wind ) and blew-up three more bullets. On to field mice at 200 yards. It’s about noon and 86˚ I again missed one and blew-up one bullet..
But in the 80 degree range only 3550 or they will come apart. Note: the 80 grain Hornadys I have were from a prototype run, The current production 80 grain Hornady A-Max’s Are of a newer design. They tell me that they are good for well over 3600; I will try some as soon as I shoot this 8000 up.
( I tried 3 at 3700 fps. In the early A.M. at 100 they cloverleafed, I think the group was about .230” ).
I’m now shooting 90 grain Berger VLD’s. The velocity is about 3370 fps (That’s at 303,300 rpm range ) But I’m still in the testing in the heat. The Bergers will come apart at 3425/3450. ( That’s 310,000 rpm ) As I shoot at sea level I do not know how altitude is going to affect them.
Somebody told me that the 90 Sierra’s had a thicker jacket and would take noticeably more velocity. Well I ordered 500 and they will shoot about 25 to 40 fps faster than the Bergers before they blowup. I called the Sierra folks and was told that they were designed for the .223/90 combo at approx 2800 fps. The same as the Bergers and that the jacket was the same thickness as the Bergers, just a little different in design.
All three of the above mentioned bullets will shoot at .500” or less at 100 yards. I’ve had 2’s, 3’s and 4’s with all of them.
My powder of chose for the .2247L is Re-22. I have found that the 47L case is not finicky; I have had some success with H-4350, N160, Re-19 also N204.
( Try to keep your loads in the 270,000 rpm range and you will not blow-up bullets ) As an example the 6mm 105/107 VLD’s seem to shoot best at 2950 to3050 fps. That would be from 265,000 to 274,000 rpm in a 1 in 8 twist barrel. Every bullet weight has it’s own optimal rpm, the lighter the bullet the faster you can spin it.
I also would like to mention that I use moly on every bullet I shoot. I love the stuff!
Until next time, John
Reply with quote #16
You have found and provided detail on the primary cause of bullet failure. The primary cause of bullet failure is high velocity combined with fast twist rates resulting in RPM that the bullet cannot handle. The key to all of this is finding out the RPM that is the limit for each bullet. We are working on this now. I believe we will discover like you have that there is a point where below a certain RPM bullets will not fail. Then you come to the RPM range where some to most bullets will fail. Lastly we have the RPM point where all bullets will fail.
Producing these data charts (RPM ranges) is a project that we are working on right now. I request of all shooter reading this that if you have experienced bullet failure please let me know the bullet, velocity and twist rate. You can either post this data here or email it to me at firstname.lastname@example.org.
It will take some time to put this all together. Once it is done we will have a clear picture of the RPM limit of each bullet. At the same time we are working on how we can increase the RPMs that a bullet can take without negatively affecting accuracy.
Thank you John for your hard work on this subject.