Two distinct groups with the same load - what's happening?
10-05-2017, 07:57 PM
#21
Typical Buck
Thread Starter
Join Date: Jul 2016
Location: Martin, TN
Posts: 854
Here's what I'm thinking: load 30 to 50 rounds with 55.0 grains of powder and the bullet seated to 3.405", clean the bore, and tighten the action screws. Fire five rounds off my Lead Sled, holding the rifle the same way every time. If they're still double grouping, I'll shoot five rounds off my specialty pistol rest and a sandbag. If that doesn't work, I'll run inside and adjust my seating depth. Lather, rinse, repeat until I find the answer.
10-06-2017, 09:35 AM
#24
Boone & Crockett
Join Date: Jan 2004
Location: Eastern PA
Posts: 12,745
My favorite 270 load was 54 gr of IMR4350 under a Nosler 130 gr Ballistic Tip. Just about every 270 that shot this load found it to be extremely accurate. So if that Enduron powder equals 4350 then you should be well within the ballpark for a decent load.
IMO if I were you I'd listen to RR. He seems pretty knowledgeable.
IMO if I were you I'd listen to RR. He seems pretty knowledgeable.
10-06-2017, 02:33 PM
#26
Nontypical Buck
Join Date: Feb 2003
Location: Eastern wv
Posts: 3,644
ok just checked the msds for 4451, its a double based powder, this means it contains nitrocellulose and nitroglycerine, its more temp sensitive than single based powders (4350 or 4831) would also try H4350. single based powders are harder on barrels than the double based but not much of a difference till you get big jugs. you won't see a difference in a 270.
RR
RR
10-06-2017, 04:02 PM
#27
Typical Buck
Join Date: Jul 2017
Location: WI&UP
Posts: 751
I will group shots with a clean barrel, and then have POI move after 3 or 4th shot.
More rounds, just to make sure you don't have some outlyers. Even with lead sled it can happen.
Not sure if you need to do 30-50. But I would fire some more. Letting barrel cool 10 minutes between shots, if you want the most accuracy. Fire a 10-20, and see what it looks like.
Another option, is to try another load or bullet.
If loaded the same, I don't believe it is actually producint 2 groups. You just got 2 bullets near each other, out of 5. Shoot some more.
I also say to watch how you are grabbing the trigger. Square your finger with it. Make sure not pulling it to one side. Again, I notice this more in handguns. But same idea.
Speaking from my bowels, I think seating depth is a different discussion.
Clean barrel. shoot 3 rounds. Then shoot 10 or more and see what you got. I like to number mine, more so for fouling shots, and as things get dirty.
More rounds, just to make sure you don't have some outlyers. Even with lead sled it can happen.
Not sure if you need to do 30-50. But I would fire some more. Letting barrel cool 10 minutes between shots, if you want the most accuracy. Fire a 10-20, and see what it looks like.
Another option, is to try another load or bullet.
If loaded the same, I don't believe it is actually producint 2 groups. You just got 2 bullets near each other, out of 5. Shoot some more.
I also say to watch how you are grabbing the trigger. Square your finger with it. Make sure not pulling it to one side. Again, I notice this more in handguns. But same idea.
Speaking from my bowels, I think seating depth is a different discussion.
Clean barrel. shoot 3 rounds. Then shoot 10 or more and see what you got. I like to number mine, more so for fouling shots, and as things get dirty.
10-06-2017, 04:04 PM
#28
Typical Buck
Join Date: Jul 2017
Location: WI&UP
Posts: 751
I was reading Lyman 47th. Different approach to test hunting loads. Fire 4 shots kinda quick. Cool down. Then put target over old, and do it 10 more times or so. This is more extreme then what I do. But the idea is to learn what your hunting rifle and load will do.
