Bushings difference in accuracy.

what is the difference between a regular NM bushing and Angle bore bushing and what is better for more accuracy??

The NM is just marketing blah as far as i know.   A gunsmith could fit a straight bore, angle bore, or spherical bushing. I'm 99.9% sure accurate guns have been made with all the above bushing types.

Which is better... no clue.

I have gravitated to a Briley bushing. Easy to get a perfect fit. Just have to keep them well oiled.

I used an EGW angle bore for my stock RO9 2 years ago cutting my group size in half at 25 yds.  I don't think the manufacturer matters as much as the fit.  My stock bushing had .002 clearance whilst my EGW is nearly an interference fit.  +1 for keeping them wet.

I too have gravitated to the Briley Bushing. I don't get their suggested ring size of .001 over barrel dimension and use .000 or -.001 and fit the barrel to the ring. I don't like how loose the ring fits in the bushing and one of these days I intend to make a ring from Aluminum Bronze to fit into the Briley outer bushing.
 The Accuracy is dependent upon how well the bushing is fitted. From what I understand though never used one is that the Angle Bored bushing is bored twice, one at the angle the barrel is at lock-up and the other at un-locked. Problem I see is that it's dependent on how the slide and barrel is made. If the angles used to make the bushing are different than the angles that resulted when the barrel is fitted to the slide then the fit will not be good.  I have double bored bushing in my Jig Borer matching the angles developed by mating of the barrel and the slide. However it's quite time consuming and a Jig Borer is needed, though not as accurate a good milling machine can be used.

Greetings,

The original Military designation for National Match bushing was one that was intentionally machined oversize and required fitting.

Some contracts specified a National Match barrel with a bushing honed to match the barrel as an assembly. I have several of these. Again, the barrel relief and fitting to the slide still had to be done.

I get a laugh when reading about "National Match" Glock parts. I have never seen a Military drawing to support such items.

Cheers,

Dave

The angle bore bushing is a huge time saver for fitting to barrel. The angle allows the barrel to lock and unlock (up and down vertically) with no barrel springing. A straight bore bushing like the NM requires relieving in specific places to allow the same vertical travel (barrel locks into slide lugs and drops out/down during cycling.
I don't like Briley bushings because of the extra tolerance (spherical ring to bushing). They all will shoot accurately when properly fit.
Jon

What are the benefits or detraction's to a split bushing ?

Multiracer wrote:What are the benefits or detraction's to a split bushing ?

Assuming old school collet bushing? It's been too long since I've messed with one. Used to be standard on Gold Cups. They're known to break on occasion. Didn't always fit slide snug enough. 
Jon

fc60 wrote:Greetings,

I get a laugh when reading about "National Match" Glock parts. I have never seen a Military drawing to support such items.

Cheers,

Dave

I used to get a laugh at the suckers who paid extra for a "National Match" AK-47.  

Jon Eulette wrote:

Multiracer wrote:What are the benefits or detraction's to a split bushing ?

Assuming old school collet bushing? It's been too long since I've messed with one. Used to be standard on Gold Cups. They're known to break on occasion. Didn't always fit slide snug enough. 
Jon

Thats the one, four slots cut in the sidewall, kind of a spherical contact point inside.

Yep collet bushing.
Jon

they were not known for accuracy..  Never saw one in a BE pistol