MichalS

What is the case fill? With RS62 and 147ELD @2,80" I get compressed loads around 43 grain.

Update - I'm in the proccess of ordereing a Sabatti simikar to one I've been shooting in 308. Will update if/when the rifle will be ready.

Dear Sirs,

As I recently acquired an AR 10 in 6.5 CM I'd like to add a bolt action in the same calibre. I was reading rave revievs of Tikka Tac A1 - is it really that good? Another option I'm considering is Bergara BMP which also seems to be a popular option. Rifle will be used for precisiin target shooting.

Michal

Tested the above load at 300m yesterday with no wind, got 0.72MOA @300m, I think its respectable for a semi auto? Temperature was 12°C lower then the last time and I only lost a couple of m/s.

Results are in. Range temperature was 32°C. Velocity is fine, SD's are fine but the groups leave a lot to be desired. Tgere was a bit if wind, so I'll bkame it on that and retest the most promising ones... Best group (below) was 0.73 MOA with perfect vertical. Flattend primers at 42.0gr, primer cratering at 42.8gr.

Michal

It's warmer than expected... Will report the results.

Thats an option, first I'll try shooting the ones I prepered, compresion starts around max book load, I may find a node just below. I'm shooting later today, it's supposed to be 32°C so fingers crossed

How long are You seating them? I'm shooting semi auto, so COAL limited to 2.80"... What speeds are You getting? I'm using lower capacity brass (S&B, similar weight to Lapua). All data on VV site are for Lapua brass and short COALs, thats why I'm so intrigued by the 46gr load they published.

Michal

I started experimenting with N160 in 6.5CM

The book max for 139 Scenar is 42.1gr at 2.717" COAL. I got a bit surprised when I heard a cracking noise of compressing powder as the data don't indicate it should be compressed... What's even more interesting is that Scenar 136L data go up to 46.0gr...

Anyone have experience with compressed loads of N160?

TIA,

Michal

It is possible to shoot 77gr SMK to 800m. My friend recently shocked the competition by shooting 1.0MOA group at 800m with factory GGG 77gr ammunition from a 24" AR15!!! But, and that is a big but, there was no wind. None.

I plan on doing a similar thing (shooting 223 to 900m) and chose 80gr SMK as it is the highest BC bullet my twist (1:8) will handle. If I were building the rifle from scratch, I would go 6.5 twist .223AI for 85-90 grainers. By then though You have to consider if 6br is not a better option....

Michał

Brilliant results. Thw question is how it will perform with heavier 140gr class bullets? Regarding WL velocity, I had similar underestimation with RS52 and 155gr Scenar in 308Win.

NigelM, thats very usefull! Now I just have to find RL16.... The only easly available powders around here are VV, RS and Norma.... Doest anyone have experience with Norma 204 regarding temperature sensitivity?

Can anyone recommend teperature stable 6.5 Creedmoor powders that are actually aviable in Europe?

Yes, semi auto gas gun (AR 10). RS load data gives 44.8gr (sic!) as the max load for 140's with LR primer in Hornady brass...

It seems the S&B primers are the weak link. I repeated the experiment today and again got cratering and a pierced primer, this time @42.5gr RS62. I did another set with the same load (41.5-43gr RS62), 140gr Berger LRBT and Federal GM primers and was able to get ~835m/s @43.0gr (~2750fps) with no pressure signs. Groups were awful though. Got good grouping with 139 Scenar @42.0gr/805m/s (0.35MOA), I will push it further with GM primer.

Edit: On closer inspection there is a bit of cratering @43.0gr (nearest row).

Firing pin seems to be OK. Would You fire the next loads?

Today I tested my first 6.5CM loads with 139gr Scenar in Stag 10 AR, Hornady LRP brass (S&B primer). I prepared 25 cartridges, starting at 41.5gr and finishing at 43.5gr every 0.5gr to plot the velocity. COAL 2.80". According to RS load data max load in this combination is 44.8gr RS62, so I thought I was conservative.

First 4 shots @41.5gr were fine, with MV in the 795-800m/s. On the fith shot with the same velocity the primer pierced. MV was 794m/s and the shot actually went inside the earlier group...

Was it a defective primer? Shall I ignore it and continue?

Michal

Tank Hunter, thanks for the compliment, I'm flattered. I love both the trigger pulling and technical/reloading aspects of the sport, and like to discuss both. BTW this forum is a great source of information with lots of knowledgable users willing to share their experience, something I think we lack "at home".

Regarding the accuracy of .308Win I managed to extract form my package - the average of 3 three 10 shot groups at 300m, 600m and 800m ended up being 0.543MOA. I think all 3 groups would be ~0.25-0.3MOA at 100m, which is btilliant for a stock factory rifle as far as I'm concerned.

Michal

On 7/24/2019 at 8:52 AM, ronzi83 said:

So i got this from swiss reload 

Temperature coefficient          m/s pro K

RS36	7.62mm x 39	0.60
RS40	.223 Rem	0.45
RS50	.308 Win	0.70
RS52	.308 Win	0.55
RS60	8 x 68 S	0.25
RS62	.270 Win	0.90
RS70	.300 Win Mag	0.45
RS76	7mm Rem Mag	0.20
RS80	.338 Lapua Mag	0.20

 

Can anyone comment on those numbers? I'm just starting 6.5CM load development with RS62 and it got me really worried as I shoot beetween 0-30°C...

Michał

Yes, Dolphins are very popular. I was actually going to get one for FTR too,  but with the way my Sabatti is shooting I dont really see a point. Maybe one in .300WSM for open/magnum...

Thank You all for Your input, and I wanted to give You some feedback.

As suggested, I decieded to stay with the scope as there was a considerable risk I can get one with even higher "correction factor". I wasn't aware the issue is so widespread, I guess people don't trust their shooting enough to question other factors, as I did in the beggining.

Afeter taking this "correction" into equation, and gathering some more MV/velocity data I managed to score bronze at this years Sniper (no sighters, no shot marking,  You may be lucky to see Your shots in the scope at 300m if theres no mirage) Nationals with 284/300pts, 3 point off the winner. Elevations were almost perfect, but the wind I underestimated have pushed me slightly to the left.

I'm also really proud I managed to win FTR with 298/300 (new record) and average group size of 0.543MOA for all 3 distances.

Thanks again!

Michal

Version 1.0, configured with optics for ammo testing. We'll see if it shoots...

Back from the range - it shoots. Factory GGG 77gr. Still room for improvement.

From what I read, with Remington You have to swap half of the rifle for it to start shooting. I found a Savage 12 in 300wsm - maybe thats a better option?

I fancy a magnum, but want to do it with reasonable budget. Is there a factory rifle worth looking into in 300 Winchester Short Magnum?

Michal

Unfortunatelly the rifle is not ready yet. I concentrated on F Class (managed to win FTR nationals 2 weeks ago!) and stoped nagging my stock builder ... Now I'm going to turn my attention to this project.