|
|
02-29-2024, 12:03 AM
|
Member
|
|
|
Join Date: May 2008
Posts: 259
Likes: 1,373
Liked 138 Times in 85 Posts
|
|
RNFP vs. SWC
Should there be any difference in loads for 158 gr. SWC and 158-160 gr. RNFP bullets, given the same or nearly so Brinnel hardness?
I will be ordering commercial cast bullets of that weight range.
As I understand it, reasoning for adopting the SWC shape rather than round nose was the SWC was more "effective" on flesh and bone targets.
Are the current RNFP shapes more "effective" than round nosed bullets, or will I be better served by sticking with the old standard SWC shape?
|
The Following User Likes This Post:
|
|
02-29-2024, 01:12 AM
|
Member
|
|
|
Join Date: Jan 2008
Location: Harlem, Ohio
Posts: 14,465
Likes: 23,553
Liked 26,397 Times in 9,153 Posts
|
|
I use RNFP's in 45 handgun and 45-70. These are my loads for plinking, and SASS competition. They don't have much expansion, but a hunk of lead the size of your thumb shouldn't need much expansion! This design feeds well in almost every gun there is, Yet is safe to use in guns with tubular magazines.
Full and semi wadcutters were developed with shooting paper in mind, and they give crisp round holes. Regular RN bullets just give a tear to the paper and are hard to measurer for dispute resolution. RNFP won't have sharp edges to the holes in paper.
The formula for muzzel energy is:
Weight in grains X velocity in FPS X velocity in FPS, divided by 450240, Equals Energy in Foot Pounds (E=MC squared)
The Taylor Knock Down factor is Weight in grains X Velocity in FPS X Diameter in inches (.000)
These are just 2 of the many ways to judge the mechanical function of ammunition.
Bullet design influences the damage a bullet can deliver, in theory!
IN THEORY, THERE IS NO DIFFERENCE BETWEEN THEORY AND REALITY!
In reality there always is a difference!
Ivan
|
The Following 4 Users Like Post:
|
|
02-29-2024, 01:40 AM
|
Member
|
|
|
Join Date: Feb 2021
Posts: 239
Likes: 0
Liked 253 Times in 126 Posts
|
|
As stated, wadcutter and semi-wadcutter bullets were develop[ed to cut clean holes in paper. They also, however, cut large wounds channels for hunting. Generally, the Larger the meplat, the better for hunting, outside expanding bullets.
Full wadcutters tend to lose stability fairly soon, making semi-wadcutters a better choice for game.
|
The Following User Likes This Post:
|
|
02-29-2024, 02:09 AM
|
|
Member
|
|
|
Join Date: Jan 2011
Location: NM home; Tbilisi work
Posts: 5,180
Likes: 11,922
Liked 11,701 Times in 3,558 Posts
|
|
My revolver business load is the Buffalo Bore 45 Auto Rim 255 grain LRNFP. Not worried it will be inadequate.
|
The Following User Likes This Post:
|
|
02-29-2024, 04:23 AM
|
SWCA Member
|
|
|
Join Date: May 2008
Location: Peoples Republic of Calif
Posts: 4,672
Likes: 1,236
Liked 6,045 Times in 2,154 Posts
|
|
Shot placement and adequate penetration are MUCH MORE important than bullet shape. Once you get down to bullet shape of the choices listed the RN will be the least effective antipersonnel round all other things being equal, the RNFP will be somewhat better and the SWC better still.
|
The Following 2 Users Like Post:
|
|
02-29-2024, 07:20 AM
|
|
Member
|
|
|
Join Date: Feb 2010
Location: SW Oklahoma
Posts: 152
Likes: 3
Liked 378 Times in 101 Posts
|
|
Given the same bullet fit to the throats and like hardness the difference in pressure and therefore load data, theoretically since you don’t have pressure measuring equipment, will be based on case capacity.
The bullet design having more of the bullet weight outside the case will produce less pressure due to having more case capacity. Part of the reason Elmer Keith and Veral Smith designed bullets with a large proportion of the bullet outside the case when crimped in the groove. Think of a 158 RN with approximately half the bullet outside the case compared to a 158 full wadcutter with 90 percent of the bullet seated inside the case. The same powder charge is confined into effectively half the case capacity, therefore the same powder charged will produce more pressure.
The difference between commercially available bullets likely won’t make enough difference to matter in your case as far as load data is concerned.
As far as effectiveness is concerned the larger the meplat or flat on the nose is going to be more effective as a general rule. Given like meplat sizes it will be hard to tell a difference at 38 special speeds. The solid full power wadcutter shouldn’t be overlooked as a viable SD bullet, you get the biggest possible meplat at the expense of accuracy out past 50 yards or so.
|
02-29-2024, 08:20 AM
|
Member
|
|
|
Join Date: Apr 2007
Location: Virginia
Posts: 8,778
Likes: 19,566
Liked 11,883 Times in 5,394 Posts
|
|
Load data should be the same so long as the distance from the crimping groove to the base of the bullet is the same, meaning the seating depth of the bullet within the cartridge case not changing the internal volume available for the powder.
As for terminal effectiveness, the semi-wadcutter is likely to cut closer to a full diameter hole than a truncated cone or round nose flat point. The advantage of the round nose flat point is in the speed of reloading, as it does not have a sharp shoulder of the semi-wadcutter which can snag on the edge of the chamber.
__________________
VCDL, GOA, NRA
Last edited by stansdds; 02-29-2024 at 08:22 AM.
|
The Following 3 Users Like Post:
|
|
02-29-2024, 08:30 AM
|
|
SWCA Member
|
|
|
Join Date: Jul 2010
Location: Midcoast Maine
Posts: 1,575
Likes: 2,055
Liked 2,195 Times in 601 Posts
|
|
I always shot SWC bullets, then I got interested in action pistol competition and much prefer plated RNFP. The reason being all my competition revolvers are cut for moonclips and RNFP are much faster on the reload then SWC. I shoot light to moderate loads almost exclusively so I don't have to worry too much about being over pressure.
|
02-29-2024, 10:44 AM
|
Member
|
|
|
Join Date: Feb 2007
Location: SW MT
Posts: 6,738
Likes: 10,519
Liked 6,034 Times in 2,972 Posts
|
|
The RNFP was developed by Veral Smith who claimed that since there was more weight outside of the case, it provided more case capacity for powder.
If you choose to load them differently, I would only do so minimally as there is a ton of data for the swc's.
__________________
Front sight and squeeze
|
02-29-2024, 11:23 PM
|
|
Member
|
|
|
Join Date: Aug 2007
Location: between beers
Posts: 8,892
Likes: 4,779
Liked 6,943 Times in 3,312 Posts
|
|
I'd use either.
A flat point delivers energy to the target.
__________________
it just needs more voltage
|
02-29-2024, 11:26 PM
|
Member
|
|
|
Join Date: Dec 2018
Location: East Tennessee
Posts: 1,403
Likes: 1,354
Liked 3,196 Times in 899 Posts
|
|
I interchange RNFP and SWC 200 grain with no issues. Load data is the same and in my 1911’s the RNFP feeds perfectly.
|
The Following User Likes This Post:
|
|
03-01-2024, 02:03 AM
|
|
US Veteran
|
|
|
Join Date: Nov 2012
Location: Reno Nv
Posts: 13,411
Likes: 3,192
Liked 12,777 Times in 5,693 Posts
|
|
For years I shot the lead RN bullets, since they were lower in cost and
they also went into my revolver cylinder, easier, than the swc design.
Today I use the 158 lead swc design, since the holes in my paper targets
are a lot easier to measure , see and score, if needed.
The 148 HB or BB design is also very good for scoring and seeing a hole at 25 yards
vs a LRN, if used.
However, I learned that a very slow 148 BBwc out of a M49 38 special snub nose
with a minimum load of Trail Boss, Red Dot, w231 etc. will tear a paper target, without any backing, making for a por grade target result.
|
03-01-2024, 03:32 AM
|
Member
|
|
|
Join Date: Aug 2009
Location: Seattle
Posts: 3,422
Likes: 1,008
Liked 3,595 Times in 1,521 Posts
|
|
Quote:
Originally Posted by .38SuperMan
I interchange RNFP and SWC 200 grain with no issues. Load data is the same and in my 1911’s the RNFP feeds perfectly.
|
I'll remember this. I have a 10mm 1911A2, and it is a woods pistol in bear/cougar/moose country. I realize it just might anger the moose as he tramples me......
__________________
NRA RSO
|
03-01-2024, 11:05 AM
|
|
Member
|
|
|
Join Date: Nov 2011
Location: Baton Rouge, La.
Posts: 6,874
Likes: 7,481
Liked 8,136 Times in 3,679 Posts
|
|
Shoot a few of each in your gun and use the bullets it likes best .
I like the wadcutter for under 25 yard target loads .
The SWC for general all-around use ... because I was brought reading the works of Elmer Keith and Skeeter Skelton .
The RF shows it worth when you want fast easy reloading and for loads in Lever Action rifles ... they feed quite smootly .
To me the old RN design is the least effective on targets , the flat spot (Meplat) adds to a bullets hitting power and the more flat spot ... the harder the hit .
The RN design tends to "slip through" flesh .
The RN can be accurate , but it leaves a ragged hole for scoring
but a lot of game and bad guys have succumbed to round nosed bullets .
Try them all ... every shape has it's purpose !
Gary
__________________
Certified Cajun
NRA Member
Last edited by gwpercle; 03-01-2024 at 11:12 AM.
|
The Following User Likes This Post:
|
|
|
Posting Rules
|
|
|
|
|