Shooters Forum banner

1 - 7 of 7 Posts

·
Registered
Joined
·
48 Posts
Discussion Starter #1
First, I have loaded some warm 300 gr cast bullet loads in my 45 Colt Ruger SA Bisley. I'm getting about 1250 out of a 5.5 " barrel and about 3" groups at 50 yards. The cylinder throats are all about .451. I would like to make this gun a dedicated 300 - 325 gr cast bullet hunting revolver. These groups are ok, but what is possible? I plan on sluggging my bore first to help me pick a good bullet size. I should be shooting 0 to + .001 of groove size, correct? Next, I plan on doing some fire lapping to smooth the throats and bore. Will thiss give me a measureable increase in throat diameter? Also, what should I do next for accuracy? Should I ream the throat? If so, has anyone tried the throat reamer available from Brownells? . . . or should I look at having the gun rethroated? Can I rethroat myself? Wheree can I get the proper setup from for doing this by hand?
 

·
The Hog Whisperer (Administrator)
Joined
·
36,434 Posts
Nathan.... STOP what you are doing.... I mean it!

The endless pursuit of accuracy can be a great source of fun and amusement.... ask any benchrest shooter.... BUT that gun is shooting very good right out of the box.

None of what you are suggesting is bad, I've had to do all of it on different guns from time to time. But if I found one that shot as well, I'd just leave it alone and enjoy.

Just my opinion. You have already achieved much more with that gun than most people hope for.
 

·
Super Moderator
Joined
·
3,366 Posts
Nathan,

Brownells sells the reamer kit for your cylinder throats on that Ruger .45 Colt. Beartooth has the lapping supplies for your fire lapping project. And to answer your question about fire-lapping increasing throat diameter in your cylinder. Fire lapping doesn't really enlarge your cylinder throats hardly at all, for the simple reason that for every six bullets being shot down your barrel to remove bore constrictions, only one is pasisng through each cylinder throat. As a consequence you've got six times the lapping action in the barrel as in each cylinder throat... you'll need the reamer, or to open it up with a split shaft and emery cloth... time consuming, but very effective as well.

Hope this helps!

God Bless,

Marshall
 

·
Registered
Joined
·
107 Posts
Hello Nathan-

I'll offer my two cents worth for your consideration. I truly understand wanting to have my equipment performing at its best.

#1. Slug the bore. I bought an inexpensive mould from LEE Precision to cast .458 round balls (should be under $12 bucks new with handles included) and cast a few from pure lead. These are just the right size to force through the bore to get good measurements. Same goes for slugging each cylinder throat.

First thing for top accuracy - verify that the cylinder throats are larger than the groove diameter of the bore. If not - open the cylinder throats so they're at least .0005" larger than groove diameter.

Second - While you're slugging the bore - feel to see if there is any constriction where the barrel mates to the frame. The Rugers seem to have a reputation for this as they use a very tight crush fit. Fire lap as needed to remove the constriction.

#2 Select the sized diameter of the bullets to be the same as the THROAT diameter - or not more than .0005" under if they will not chamber easily. Two good things happen by doing this. 1. The bullet is forced to be concentric with the bore. 2. The bullet occupies the entire (or near entire) space in front of the powder. This in turn prevents gas cutting on the base of the bullet and avoids leading. Hard alloy is not needed or usually even desired at handgun velocities. Something on the order of air cooled WW metal is more than enough for loads to at least 1300fps.

#3 If the trigger has not already been addressed - this warrants serious consideration. It is very difficult to shoot up to the potential of the gun if you are fighting a creepy, inconsistant, or overly heavy trigger pull. If you know what you're doing - you can do the work yourself. If not - find a good gunsmith and have someone that does know what they're doing take care of it

Once these issues are addressed - test a few loads and find out what the gun likes. I've found that getting to 1.5" to 2" off sandbags is regularly possible at 50 yds. At that point - cosistency of grip and sight picture with open sights are far overshadowing my ability to wring out the equipment any further.

Good luck to you in your efforts!

Best regards-

Sky C.
Longmont, CO
 

·
Registered
Joined
·
48 Posts
Discussion Starter #6
Thanks for the help. It looks like I need to go in order. First slug my bore to check for a constiriction. Then, firelap to remove and smooth bore to eliminate leading. BTW, I have some D&J bullets which are .452. Will they be soft enough for firelapping? Also, what is an ideal firelapping velocity? Then, slug agian to get bullet size. i.e. groove size. At this point, it may need to be re-throated, if a bad constriction still exists, correct? Last, if needed, ream cylinder's to .4525. Will the .448 bushing work, or do I need the bushing pack too? Also, how are you holding the reamer? In a tap holder?
 

·
Registered
Joined
·
48 Posts
Discussion Starter #7
Sky C. said:
Hello Nathan-

Once these issues are addressed - test a few loads and find out what the gun likes. I've found that getting to 1.5" to 2" off sandbags is regularly possible at 50 yds. At that point - cosistency of grip and sight picture with open sights are far overshadowing my ability to wring out the equipment any further.

Good luck to you in your efforts!

Best regards-

Sky C.
Longmont, CO

Good accuracy. What was the before accuracy?
 
1 - 7 of 7 Posts
Top