HuntingNut
HuntingNut
   Login or Register
HomeCommunity ForumsPhoto AlbumsRegister
     
 

User Info

Welcome Anonymous


Membership:
Latest: dejan
New Today: 1
New Yesterday: 0
Overall: 12370

People Online:
Members: 0
Visitors: 184
BOT: 4
Total: 188
Who Is Where:
 Visitors:
01: Forums
02: Photo Albums
03: Forums
04: Forums
05: Forums
06: Forums
07: Forums
08: Forums
09: Forums
10: Photo Albums
11: Forums
12: Forums
13: Forums
14: Photo Albums
15: Forums
16: Forums
17: Forums
18: Forums
19: Forums
20: Forums
21: Photo Albums
22: Forums
23: Photo Albums
24: Forums
25: Home
26: Forums
27: Forums
28: Forums
29: Forums
30: Forums
31: Forums
32: Forums
33: Forums
34: Forums
35: Photo Albums
36: Forums
37: Your Account
38: Forums
39: Your Account
40: Forums
41: Forums
42: Photo Albums
43: Forums
44: Forums
45: Forums
46: Your Account
47: Forums
48: Forums
49: Forums
50: Forums
51: Forums
52: Forums
53: Forums
54: Forums
55: Forums
56: Forums
57: Home
58: Forums
59: Forums
60: Forums
61: Photo Albums
62: Forums
63: Forums
64: Forums
65: Forums
66: Forums
67: Photo Albums
68: Forums
69: Forums
70: Forums
71: Forums
72: Your Account
73: News
74: Forums
75: Forums
76: Forums
77: Your Account
78: Home
79: Photo Albums
80: Forums
81: Forums
82: Forums
83: Photo Albums
84: Forums
85: Forums
86: Your Account
87: Forums
88: Your Account
89: Photo Albums
90: Forums
91: Forums
92: Forums
93: Forums
94: Photo Albums
95: Forums
96: Forums
97: Photo Albums
98: Your Account
99: Photo Albums
100: Forums
101: Photo Albums
102: Forums
103: Forums
104: Forums
105: Forums
106: Forums
107: Photo Albums
108: Forums
109: Forums
110: Forums
111: Photo Albums
112: Forums
113: Your Account
114: Forums
115: Forums
116: Forums
117: Forums
118: Forums
119: Home
120: Forums
121: Forums
122: Photo Albums
123: Photo Albums
124: Photo Albums
125: Forums
126: Forums
127: Forums
128: Photo Albums
129: Forums
130: Forums
131: Forums
132: Forums
133: Forums
134: Forums
135: Your Account
136: Photo Albums
137: Forums
138: Forums
139: Forums
140: Forums
141: Forums
142: Forums
143: Forums
144: Forums
145: Forums
146: Forums
147: Photo Albums
148: Forums
149: Forums
150: Forums
151: Forums
152: Forums
153: Forums
154: Your Account
155: Home
156: Photo Albums
157: Forums
158: Forums
159: Forums
160: Photo Albums
161: Forums
162: Forums
163: Forums
164: Forums
165: Forums
166: Photo Albums
167: Forums
168: Forums
169: Photo Albums
170: Forums
171: Home
172: Forums
173: PointBlank Ballistics
174: Photo Albums
175: News
176: Photo Albums
177: Forums
178: Forums
179: Forums
180: Forums
181: Photo Albums
182: News
183: Forums
184: Forums
  BOT:
01: Forums
02: Your Account
03: Forums
04: Forums

Staff Online:

No staff members are online!
 

Coppermine Stats
Photo Albums
 Albums: 312
 Pictures: 2415
  · Views: 246900
  · Votes: 1255
  · Comments: 86
 

Support our Advertisers

OAL gauge question
Discussion regarding the reloading of ammunition and tuning of loads for accuracy
Post new topic   Reply to topic   Printer Friendly Page    Forum Index » Reloading Ammunition

View previous topic :: View next topic  
Author Message
dakota1
Member
Member


Joined: Aug 09, 2007
Posts: 37
Location: Mesa, Arizona

PostPosted: Thu Sep 20, 2007 9:56 am    Post subject: OAL gauge question Reply with quote

I received my OAL gauge yesterday. Using the modified case I ordered with it, I checked my maximum OAL. I am loading .270 Win, 130 gr BTSP Sierra bullets. Due to the boattail design, when the bullet is pushed against the lands, it is actually pushed out of the case. I think that if the bullet was a flat base it would stay in the case.

I checked to make sure the modified case would fit, by chambering it with the bolt. I cleaned my gun before measuring. I used a light finger tap, as suggested, for the bullet seating on the lands.

Is this common, or am I doing something wrong?

Thanks.
Back to top
View user's profile AIM Address
DallanC
Site Admin
Site Admin


Joined: Jan 18, 2005
Posts: 3078
Location: Utah

PostPosted: Thu Sep 20, 2007 10:16 am    Post subject: Re: OAL gauge question Reply with quote

Its called "freebore", the distance from the bullet to where the lands start. Some rifles design in alot of freebore to get the bullet moving before it engages the lands, Weatherby for example is famous for this. Others like the bullet to engage quicker so the lands are cut closer to the bullet.

It can be common though for there to be alot of freebore in a factory rifle where a person might shoot various bullet types which would require more or less freebore just to fit in the bullet.

Bottom line is accuracy... I have accurate rifles with a ton of freebore and some with crappy accuracy with alot of freebore so shoot yours and find out where its at. I believe you can get a good gunsmith to remove your barrel, cut it down where it threads onto the action and "set back" the rifle X distance to give you less freebore. One of our resident experts can give you more info on that... or if its cheaper to just buy a new barrel.


-DallanC
Back to top
View user's profile Photo Gallery
dakota1
Member
Member


Joined: Aug 09, 2007
Posts: 37
Location: Mesa, Arizona

PostPosted: Thu Sep 20, 2007 10:29 am    Post subject: Re: OAL gauge question Reply with quote

Thanks Dallan.

It's a Remington 700 BDL rifle. I didn't realize they barreled them with that much freebore. Kind of makes a Stoney Point OAL gauge a mute point.
Back to top
View user's profile AIM Address
hunterjoe21
Super Member
Super Member


Joined: Mar 30, 2007
Posts: 1230
Location: North Central Montana

PostPosted: Sat Sep 22, 2007 6:39 pm    Post subject: Re: OAL gauge question Reply with quote

I wouldn't discount the use of the OAL guage. When used with a bullet comparator, it will assist in seating bullets to an accurate depth and measuring true freebore. Measuring CARTRIDGE OAL with a caliper does little to ensure a consistent seating depth. There are too many variations in bullet design, and especially with HP and SP bullets, variations from bullet-to-bullet. Measuring COMPARATOR overall length gives you an accurate and repeatable measurement, which will allow you to "tweak" the freebore until you find the distance that works in your particular firearm.

As for a bullet being too short to be seated close to the rifle's lands, it is NOT uncommon to find certain light-for-caliber bullets that don't reach the lands. I had the same issue loading 40 gr. bullets for a .22-250, and even though factory loads produced decent groups, I was never able to find the right powder/primer combo to duplicate factory performance. Once I Moved up to 50 gr. bullets, I was quickly able to solve accuracy issues, mainly by seating the 50 gr. bullets closer to the lands than the 40 gr. bullets would allow.

_________________
My 1911 is more effective than your 911.
Back to top
View user's profile
dakota1
Member
Member


Joined: Aug 09, 2007
Posts: 37
Location: Mesa, Arizona

PostPosted: Sun Sep 23, 2007 7:41 pm    Post subject: Re: OAL gauge question Reply with quote

I rechecked my chamber, and I must have been letting the case back out, or not inserting fully, during measurement. I have been able to repeat the measurement and have found the chamber capable of seating a 130 gr boattail againt the lands. I am not planning on doing so at this time, but it is nice to know that I now have an accurate measurement.

I do have another question. I have read that a comparator would compliment the OAL gauge, for an accurate measurement from the head to the ogive. I see that Hornady has a comparator body and inserts, which seem straight forward, and the illistration shows it being used with the OAL gauge, again straight forward. What is the Anvil base kit for? Is this to be attached to your caliper so OAL can be done with an actual loaded round? Sinclair has a comparator that looks like a hex nut. Any opinions? Likes or dislikes of either?

Is this benchrest stuff, or can a hobby shooter, with a 700 BDL actually benefit?

Thanks for any input.
Back to top
View user's profile AIM Address
Deleted_User_2665
Super Member
Super Member


Joined: May 06, 2006
Posts: 380

PostPosted: Mon Sep 24, 2007 6:09 am    Post subject: Re: OAL gauge question Reply with quote

Re: Remmy 700's less a custom barrel, ie factory.

Seat to function through the mag box....for starters, with at least a full diameter width of bullet seated in the neck.

With that variable set in stone for the time being begin load developement, adjust charge weight per OCW practices to glean The Sweet Spot.

If need be, then tweak the seating depth to shrink groups if so inclined.

Intial Sweet Spot should reveal MOA groups or less....beyond that is a bonus.

Once accomplished, a solid OCW load negates much garbage others fret much......like freebore.

THE most accurate load, consistant 1/2 MOA, in my factory .270 700 BDL was 90 grain Sierra HP's, and they jumped at least a quarter inch of freebore.
Back to top
View user's profile
FALPhil
Super Member
Super Member


Joined: Aug 18, 2007
Posts: 377
Location: Dixie

PostPosted: Mon Sep 24, 2007 8:41 am    Post subject: Re: OAL gauge question Reply with quote

dakota1 wrote:
Kind of makes a Stoney Point OAL gauge a mute point.

It would be a moot point too. Very Happy
Back to top
View user's profile Photo Gallery
dakota1
Member
Member


Joined: Aug 09, 2007
Posts: 37
Location: Mesa, Arizona

PostPosted: Mon Sep 24, 2007 9:00 am    Post subject: Re: OAL gauge question Reply with quote

What is OCW?
Back to top
View user's profile AIM Address
Deleted_User_2665
Super Member
Super Member


Joined: May 06, 2006
Posts: 380

PostPosted: Mon Sep 24, 2007 5:15 pm    Post subject: Re: OAL gauge question Reply with quote

Optimal Charge Weight.....

Not widely recognized by the masses and highly poo poo'd by those who thrive on frettin' voodoo, fiddle fartin' around with numerous gadgets, and insist on taking extra steps.

If you've ever wondered why some powders are temperature sensitive, why different lots of components affect a load, why some handloaders loads are successful with a certain brand of brass but fail with others, if you've ever chased the occasional flyer while scratching your head.............then you need OCW.

It makes leaps and bounds toward negating variables that affect pressure sensitivity on many levels. Pressure, by all accounts of the Laws of Physics, is the heart of the beast.

Freebore is a variable that cannot be adjusted without a smith's help, so it is a given and is constant. Aleviating the other varibles in the equation that plague a handloader makes such things as freebore less of a concern......


If you are interested in studying the OCW principles and gaining an insight on a superb method of load development I'll PM you a link to a bestest explaination of it.
Back to top
View user's profile
guncollector
Member
Member


Joined: Apr 25, 2006
Posts: 68
Location: Houston, Texas

PostPosted: Tue Sep 25, 2007 2:10 pm    Post subject: Re: OAL gauge question Reply with quote

I shoot that same bullet in a 270 Rem 700 and got best results 0.020 off the lands. You really do need a comparator to go along with the OAL gage especially if you are getting close to the lands. A bullet with no jump space will result in significantly higher pressures relative to one with at least a few thousandths of jump.

Generally speaking, the best accuracy will be somewhere between 0.02 and 0.06 off the lands. For some reason, Barnes bullets need more jump space - typically 0.06 to 0.08 in my experience.

Something interesting I didn't know until recently was that cast bullets almost always shoot best with no jump space. A little higher pressure with them is not an issue since they must be loaded quite mild compared to jacketed bullets.

_________________
If the Government doesn't trust us with our guns, why should we trust them with theirs?
Back to top
View user's profile
Display posts from previous:   
Post new topic   Reply to topic   Printer Friendly Page    Forum Index » Reloading Ammunition
Page 1 of 1
All times are GMT - 7 Hours



Jump to:  


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum


Advertisements
 


Valid CSS! Valid HTML 4.01!
Click to check if this page is realy HTML 4.01 compliant for speed :)

All logos and trademarks in this site are property of HuntingNut.com.
The comments are property of their posters, all the rest © 2011 by HuntingNut.com
Interactive software released under GNU GPL, Code Credits, Privacy Policy

.: Upgraded to DragonFly 9.2 by Dizfunkshunal :.