6.5cm load advice

[red_squirrel]

Hi, firstly sorry for the long post!

I'm just starting out in rifle reloading, and need to choose a load for the comp at roundhouse nr bodmin next weekend. Yesterday I shot the test rounds over a magnetospeed chrono, I'd be very grateful for any help in choosing which one to load!!

Rifle Specs: Howa 1500 24" with mod.

Reloading: Rs62 powder, new starline large primer brass, bevelled, primer demurred and chamfered by hand. Run through a lyman m neck expander, primed (fiche large rifle), individually weighed powder drop and seated and crimped in lee dies on my dillon xl 650. oal 2.84.

Here is the data we recorded:

lap 139gr scenar

41.5, av velocity 2620, sd 42, .8moa

42 av velocity 2724, sd 43, 1.08 moa

42.5 av velocity 2760, sd 19, .85 moa

43 av velocity 2780, sd 22, 0.93 moa

43.5 av velocity 2835, sd 20, 1.02 moa

Hornady 140gr eld

41.5, av velocity 2567, sd 13, .48moa

42 av velocity 2679, sd 9, .9 (0.4 with 1 flyer) moa

42.5 av velocity 2686, sd 19, .71 moa

43 av velocity 2726, sd 26, 0.93 moa

43.5 av velocity 2749, sd 24, 1.01 moa

 

I had loaded 44 hrs but didn't fire them as I was getting quite a heavy bolt lift and some really defined ejector marks. I'm thinking the best in terms of sd and grouping were the 42.5 with the scenars, and the 42 with the hornady elds, but the velocity is not as high as I had expected. Will the velocity go up a bit with once fired brass? Would I be better going for the higher velocity, bearing in mind the shoot next weekend is at up to 1100yds? 

Any and all advise gratefully received :-)

 

 

 

[Steve steve]

Hi mate, i might be wrong but I would say your pressure will come down a little when using once fired brass over new

fyi I’m shooting 140gr eldms with once fired Hornady brass, cci 250 primers , 44.3gr rs62 , ABSOLUTELY NO PRESSURE SINGS 

ever so slightly compressed load seated at 2.811 oal 

i will put them over a magnetospeed one day this week and update  you but they shoot .25 MOA 

i have heard that rs62 varies a little batch to batch 

[Steve steve]

I’m surprised there is a 86fps difference coming from the Lapua bullets but again I’ve heard they’re a fast bullet down the barrel 

[markymark]

My recent ladder test with 139 Scenars and RS62 very closely mirror your results except a little higher velocity. I assume my 26” barrel is the reason. 

I just did a ladder test, I didn’t shoot groups with them. However from 40gr to 43.5gr the POI was all sub 1 MOA. 

I didn’t get a sticky bolt, however I was also seeing the ejector markings on the brass at 43gr. I going to re-run my test again at a different COAL. 

However im assuming my load will also be around 42.5gr. There or there abouts. My goal was to achieve 2750fps once I’ve got around that with a good node I’m not going to chase anymore velocity. Strelok suggest that this will achieve 1200yards supersonic. 

You say your shooting 1100yards, this load should see you well no?

[red_squirrel]

1 hour ago, markymark said:

My recent ladder test with 139 Scenars and RS62 very closely mirror your results except a little higher velocity. I assume my 26” barrel is the reason. 

I just did a ladder test, I didn’t shoot groups with them. However from 40gr to 43.5gr the POI was all sub 1 MOA. 

I didn’t get a sticky bolt, however I was also seeing the ejector markings on the brass at 43gr. I going to re-run my test again at a different COAL. 

However im assuming my load will also be around 42.5gr. There or there abouts. My goal was to achieve 2750fps once I’ve got around that with a good node I’m not going to chase anymore velocity. Strelok suggest that this will achieve 1200yards supersonic. 

You say your shooting 1100yards, this load should see you well no?

That makes a lot of sense, Hornady factory ammo goes at 2710 and my rifle seems to really like it.

The velocity of the scenarios with 42.5 gr is about what I'm looking for, so I'll load another 150 of them, but the grouping and sd were disappointing. The lower weights with the hornadys shot better groups and sd.

Will 2680fps see me supersonic at 1100?

[markymark]

Yes it should. Obviously data hasn’t been trued, but in theory it should take you to 1200yards. 

I think the load you’ve worked out so far should see you for your next shoot. I would be keen to re-test at perhaps 0.3 load up increments, look for a node around you chosen velocity then tweek seating depth to tighten up groups. 

How did you decide upon your COAL?

[red_squirrel]

Just went for max magazine length - and checked that there is no contact with the rifling. 

After the weekend I'll have time for some fine tuning.