Crimping the .308

Get or give advice on equipment, reloading and other technical issues.

Moderator: Mod

Message
Author
Tony Q
Posts: 1044
Joined: Mon Jun 20, 2005 8:04 pm
Location: Adelaide (MBRC)

Crimping the .308

#1 Postby Tony Q » Tue Jun 28, 2005 1:45 pm

Is anyone crimping their .308’s

We have a champion fullbore shooter who has recently started to crimp his loads and he has now formed a superior view on their overall accuracy.

I do believe that some issues are mentally based, if we get on the mound with the upmost trust in our equipment and ammo we shoot well. If we have any doubts we shoot badly.

For example, if I use NRAA Factory 155gn (as good as they are) I have this underlying issue in the back of my mind that they are not my trusted handloads and as such could have a bearing on my performance.

What are your thoughts?

Guest

#2 Postby Guest » Tue Jun 28, 2005 2:51 pm

tony

have you noticed any difference between shells when bullet seating (some seat with less resistance than others)

bullet crimping would remove this small inconsistency between rounds and therefore keep pressure variations to a minimum and therefore increase accuracy

that’s my understanding of it anyway (maybe I’m wrong)

Tony Q
Posts: 1044
Joined: Mon Jun 20, 2005 8:04 pm
Location: Adelaide (MBRC)

#3 Postby Tony Q » Tue Jun 28, 2005 3:11 pm

Sure, some are tight while some offer almost no resistance.

Through the chrony my max deviation is normally never more than 20fps

B.Scheske
Posts: 23
Joined: Sat Jun 25, 2005 4:36 pm
Location: Victor Harbor South Australia
Contact:

#4 Postby B.Scheske » Tue Jun 28, 2005 3:16 pm

that was me forgot to log-in

eventhough you only get 20fps deviation it might still be enough and certainly at the longer ranges

other that that you could send it to Myth Busters see what they come yp with
"Make The First Shot Count!"


Brett

Tony Q
Posts: 1044
Joined: Mon Jun 20, 2005 8:04 pm
Location: Adelaide (MBRC)

#5 Postby Tony Q » Tue Jun 28, 2005 3:19 pm

Now, for the academics out there …

Does crimping change the BC to a higher level?

The displaced lead has to go somewhere and while the diameter is a constant it can only go the nose. I would imagine it does elevate the BC but it may be immeasurable in regard to any advantage.

Also additional drag caused by the new canilure ? or should I re direct this post to the MIT or other University :lol:

B.Scheske
Posts: 23
Joined: Sat Jun 25, 2005 4:36 pm
Location: Victor Harbor South Australia
Contact:

#6 Postby B.Scheske » Tue Jun 28, 2005 3:21 pm

[quote="Tony Q"]Now, for the academics out there …

Does crimping change the BC to a higher level?

The displaced lead has to go somewhere and while the diameter is a constant it can only go the nose. I would imagine it does elevate the BC but it may be immeasurable in regard to any advantage.

Also additional drag caused by the new canilure ? or should I re direct this post to the MIT or other University :lol:[/quote]

good question hope someone can answer it cuase i would like to know to
"Make The First Shot Count!"





Brett

RAVEN
Posts: 1978
Joined: Sun Jun 19, 2005 9:37 pm
Location: Adelaide South Australia (CTV)

#7 Postby RAVEN » Wed Jun 29, 2005 12:56 am

TQ what are U waffling on about? :roll: :P
I don’t think this would have any effect on BC the bullet is rammed down a barrel at lightning speed rifling gouging into the bearing surface what is the diff of a few little scratches on the side
BC a fuggy figure at best is determined by bullet shape and metplate
I think the crimping is to do with a positive neck tension giving a uniform pressure curve
RB
If U want some real tech answers go to

http://www.benchrest.com/forums/

http://www.long-range.com/

Tony Q
Posts: 1044
Joined: Mon Jun 20, 2005 8:04 pm
Location: Adelaide (MBRC)

#8 Postby Tony Q » Wed Jun 29, 2005 8:48 am

lol Richard

I know the question was right out there in regard to reallity. The question was for those who come from another planet ... could have them thinking for weeks.
MBRC F-Class standard ... and proud of it!

RAVEN
Posts: 1978
Joined: Sun Jun 19, 2005 9:37 pm
Location: Adelaide South Australia (CTV)

#9 Postby RAVEN » Wed Jun 29, 2005 9:38 am

:lol: :lol: :lol:
Good 1 M8ty


Return to “Equipment & Technical”

Who is online

Users browsing this forum: Brett.44 and 43 guests