25 cal bullets

[blackbeard]

Does anyone know if a heavier 25 cal bullet has ever been made? the heaviest I have ever seen is 120gr.The reason I ask is, would the big cased quarter bores not benefit from a 125-135gr long skinny bullet for long range stuff.The25-06 and 257 weatherby both have more than enough powder capacity to push those heavy bullets along at a pretty good clip.Any thoughts guys?

 

[Chinbullco]

I've been experimenting with a 135, 145, 155 gr 257's. Built a 25 cal on a 300 WSM case, sized down to 300 SAUM, then necked to 25 cal. Used a 1:8 Jury barrel. Results using my 135 gr have been great. 3150 fps using Retumbo. The project slowed down when I looked after required knee surgery, but hope to compete this summer in F-open with 135gr 257 and the "Long Neck 25 SAUM". The 135's shot so good I never got around to trying the 145 and 155 gr bullets.

When experimenting with fast twist barrels and long for caliber bullets barrel length becomes important. With a fast twist barrel too long, high pressure will creep up before satisfactory velocities are realized.

 

[Boomer]

I've been experimenting with a 135, 145, 155 gr 257's. Built a 25 cal on a 300 WSM case, sized down to 300 SAUM, then necked to 25 cal. Used a 1:8 Jury barrel. Results using my 135 gr have been great. 3150 fps using Retumbo. The project slowed down when I looked after required knee surgery, but hope to compete this summer in F-open with 135gr 257 and the "Long Neck 25 SAUM". The 135's shot so good I never got around to trying the 145 and 155 gr bullets.

When experimenting with fast twist barrels and long for caliber bullets barrel length becomes important. With a fast twist barrel too long, high pressure will creep up before satisfactory velocities are realized.

I like the idea of long/heavy bullets in small bores. But I'm having some difficulty in getting my head around the idea that a long barrel with a fast twist can produce more pressure than a shorter barrel having the same twist, firing the same load. Maximum pressure occurs with the initial movement of the bullet, at which time the length of the barrel is irrelevant. This is why seating with a jump or a jam has such an effect on pressure. Maximum pressure has already been observed within the first few inches of bullet travel, and any greater barrel length simply increases the volume available to the propellant gases, and actually reduces pressure. Rather than the result of increasing pressure, higher velocity is the result of the gases expanding at +/- 5000 fps, having more time to accelerate the bullet.

My target rifle, a .308, has a 28" 1:8 Krieger barrel and the lead is purposely long so that the boat-tail of a bullet doesn't extend below the shoulder of the case. I can load this rifle much hotter, without pressure signs, than I can a .308 with a conventional lead in a 1:2 barrel. I getting 2650 (Oehler 35P) with 210 gr Matrix bullets over a stiff load of N-550, but now I've got a box of 230 gr Hybrids to play with.

 

[Chinbullco]

I like the idea of long/heavy bullets in small bores. But I'm having some difficulty in getting my head around the idea that a long barrel with a fast twist can produce more pressure than a shorter barrel having the same twist, firing the same load. Maximum pressure occurs with the initial movement of the bullet, at which time the length of the barrel is irrelevant. This is why seating with a jump or a jam has such an effect on pressure. Maximum pressure has already been observed within the first few inches of bullet travel, and any greater barrel length simply increases the volume available to the propellant gases, and actually reduces pressure. Rather than the result of increasing pressure, higher velocity is the result of the gases expanding at +/- 5000 fps, having more time to accelerate the bullet.

My target rifle, a .308, has a 28" 1:8 Krieger barrel and the lead is purposely long so that the boat-tail of a bullet doesn't extend below the shoulder of the case. I can load this rifle much hotter, without pressure signs, than I can a .308 with a conventional lead in a 1:2 barrel. I getting 2650 (Oehler 35P) with 210 gr Matrix bullets over a stiff load of N-550, but now I've got a box of 230 gr Hybrids to play with.

Kreiger doesn't make a 1:8 308 barrel for the reason I stated. I've seen this problem with several barrels and it made no sense to me either. Had problems with a 6.5 300WSM in a 1:7 twist finished at 31" and firing 165 gr ULD's. Too much pressure, disappointing velocity. Shortening barrel improved pressure problem and velocity increased. Conventional thinking would place me being retarded! Maybe? When barrel was shortened to 26" I was able to get 2950 fps with 165 gr bullet, using 66.6 gr Retumbo. Bolt opened with ease, primers still had a slight radius, no measurable case head or extractor groove expansion,(determined by before and after measurements).

Getting back to 257's. The 135 gr shot great, the 145 and 155 gr could possibly get me into the high pressure / long bullet / fast twist problems experienced with the 6.5.

 

[Boomer]

Kreiger doesn't make a 1:8 308 barrel for the reason I stated. . . .

Actually, yes they do.

 

[Chinbullco]

They don't list a 1:8 308 caliber barrel on their website. Special order?

 

[Boomer]

Yup, just like ordering a barrel longer than 28".

 

[c-fbmi]

Does anyone know if a heavier 25 cal bullet has ever been made? the heaviest I have ever seen is 120gr.The reason I ask is, would the big cased quarter bores not benefit from a 125-135gr long skinny bullet for long range stuff.The25-06 and 257 weatherby both have more than enough powder capacity to push those heavy bullets along at a pretty good clip.Any thoughts guys?

Marshal at Matrix bullets makes a catalog item 125 gn 25 cal bullet in both flat base and RBT and if he's not too busy he can make heavier ones too. Just made up a couple racks of test loads for my 25-06 with both his 125 gn bullets, weather has NOT been co-operating for shooting though.............

 

[Johnn Peterson]

I've posted this previously, but a while back I picked up a Savage 112BVSS in .25-06 and put some decent glass on it.



I 'tried' a fairly diverse selection of bullet brands and in a variety of weights and load combinations. From an accuracy standpoint alone, on a steady basis, my best results came using the Sierra 117gr SBT. Pardon the homemade target.

 

[Pathfinder]

I got some from Matrix bullets in bc, send them a message.

 

[brybenn]

Marshal at Matrix bullets makes a catalog item 125 gn 25 cal bullet in both flat base and RBT and if he's not too busy he can make heavier ones too. Just made up a couple racks of test loads for my 25-06 with both his 125 gn bullets, weather has NOT been co-operating for shooting though.............

Hope to read your findings on these bullets. I'd like to try them when I replace the barrel on my 25/06. My plan is to re barrel with a long heavy barrel for longer range shooting with heavier bullets and getting a 250 savage for lighter bullets instead of burning up another barrel

 

[Chinbullco]

I like the idea of long/heavy bullets in small bores. But I'm having some difficulty in getting my head around the idea that a long barrel with a fast twist can produce more pressure than a shorter barrel having the same twist, firing the same load. Maximum pressure occurs with the initial movement of the bullet, at which time the length of the barrel is irrelevant. This is why seating with a jump or a jam has such an effect on pressure. Maximum pressure has already been observed within the first few inches of bullet travel, and any greater barrel length simply increases the volume available to the propellant gases, and actually reduces pressure. Rather than the result of increasing pressure, higher velocity is the result of the gases expanding at +/- 5000 fps, having more time to accelerate the bullet.

Secondary powder burn? Some interesting reading on secondary powder burn on Pressure Trace' page. In their testing these secondary high pressure spikes can occur as late as one millisecond after ignition. I didn't dream up my findings, and its a PO when when someone brushes them off as BS. There is something scientifically strange happening with slow burning powder, long for caliber bullets, and long fast twist barrels. The pressure generated with 6.5-300 WSM / 165gr bullet / 1:7 X 31" bbl / Retumbo and Fed 215 resulted in extractor groove expansion of 0.008". I ordered Pressure Trace.

Anybody experimenting with similar bullets and fast twist bbls and would like to compare findings post or PM me.

 

[Andy]

Originally Posted by Boomer I like the idea of long/heavy bullets in small bores. But I'm having some difficulty in getting my head around the idea that a long barrel with a fast twist can produce more pressure than a shorter barrel having the same twist, firing the same load. Maximum pressure occurs with the initial movement of the bullet, at which time the length of the barrel is irrelevant. This is why seating with a jump or a jam has such an effect on pressure. Maximum pressure has already been observed within the first few inches of bullet travel, and any greater barrel length simply increases the volume available to the propellant gases, and actually reduces pressure. Rather than the result of increasing pressure, higher velocity is the result of the gases expanding at +/- 5000 fps, having more time to accelerate the bullet.

Secondary powder burn? Some interesting reading on secondary powder burn on Pressure Trace' page. In their testing these secondary high pressure spikes can occur as late as one millisecond after ignition. I didn't dream up my findings, and its a PO when when someone brushes them off as BS. There is something scientifically strange happening with slow burning powder, long for caliber bullets, and long fast twist barrels. The pressure generated with 6.5-300 WSM / 165gr bullet / 1:7 X 31" bbl / Retumbo and Fed 215 resulted in extractor groove expansion of 0.008". I ordered Pressure Trace.

Anybody experimenting with similar bullets and fast twist bbls and would like to compare findings post or PM me.

Your position is literally the first time I've heard of it - anywhere. Not powder manufacturers, anyone producing load manuals, gun writers, nor barrel manufacturers have stated that to the best of my knowledge, so naturally I am skeptical. I've got to say that I am with Boomer on this, but am willing to change my beliefs in response to strong evidence to the contrary.

 

[Chinbullco]

Originally Posted by Boomer I like the idea of long/heavy bullets in small bores. But I'm having some difficulty in getting my head around the idea that a long barrel with a fast twist can produce more pressure than a shorter barrel having the same twist, firing the same load. Maximum pressure occurs with the initial movement of the bullet, at which time the length of the barrel is irrelevant. This is why seating with a jump or a jam has such an effect on pressure. Maximum pressure has already been observed within the first few inches of bullet travel, and any greater barrel length simply increases the volume available to the propellant gases, and actually reduces pressure. Rather than the result of increasing pressure, higher velocity is the result of the gases expanding at +/- 5000 fps, having more time to accelerate the bullet.



Your position is literally the first time I've heard of it - anywhere. Not powder manufacturers, anyone producing load manuals, gun writers, nor barrel manufacturers have stated that to the best of my knowledge, so naturally I am skeptical. I've got to say that I am with Boomer on this, but am willing to change my beliefs in response to strong evidence to the contrary.

It is not a "position". It is something recorded and experienced. My load data and record keeping are precise. I've questioned Sierra's tech-line, Hodgdon's, and anyone else I could think of that might know. It seems all the pressure test equipment and strain pressure gauges don't show this secondary ignition. Only person that seemed to know anything on this topic was Bill Wiseman. I have had weird pressure spike issues in three barrels and three different calibers. Its not a Liberal / Conservative debate issue. I post very little on this forum because of this type of response. Reading the info on pressuretrace' page was the first I seen or heard about secondary, extreme high pressure phenomenon.

 

[c-fbmi]

I have played with the 22-284 with a 1-8 twist and 30" long barrel without any secondary pressure spikes using 80 and 90 gn bullets.........bullets are coming unglued at about 30 mtrs, but that's a whole 'nother problem. Also shooting 100 and 105 gn bullets from a 23 cal 1-8 twist 28" barrel with no signs of what you describe. As I'm sure, if you read this forum much, you will know that I'm not known to "spare the horses" when it comes to loading, so if these phenomenon were out there I surely should have experienced it by now with one or the other of these cartridges.............no?
Can you repeat this phenomenon at will? Has it happened with only one powder, or several? Can you give more detail of the theory behind this phenomenon? I'm not saying it can't happen, but this is the first I've ever heard of it, after wildcatting and amateur 'smithing for more than 40 yrs. If pressure testing equipment, which tracks the pressure curve through the entire length of the barrel, doesn't register this phenomenon, how do you explain that? People have been playing with quick twist and long barreled 6.5 and 7 mms with heavy bullets, for many, many years now and you are the first to ever encounter this pressure anomaly, how do you explain this? What is the fuel that is ignited to produce this secondary pressure wave, in order to have a secondary ignition, as you describe, there has to be a fuel source............internal ballistics and physics demands it.
As a 40 year student of internal and external ballistics, having played with many varying barrel lengths and twist rates, as well as extended flash tubes of various lengths, multiple flash holes, extended flash tube with multiple flash holes, lighting the entire center column of the powder charge, and many more weird and wonderful projects, I have never witnessed what you describe. I have also been an avid reader of Ackley and have read all he has published and much that never was published, and no where does he mention coming across such an anomaly. HOWEVER, having said this there are many new powders since Ackley's time so I do not discount what you say entirely as impossible. I just cannot wrap my head around what would be left to ignite, after 26" of bullet travel and pressure at it's virtually lowest point in a barrel, prior to exit, that wouldn't have been ignited at pressures exceeding 60,000 psi and temps at their maximum during the ignition event in that load...........and how rate of twist could affect it.
Ron Smith has been building gain twist barrels of varying lengths and twists for decades now and has never alluded to such a phenomenon. It should make sense that a long gain twist barrel would be more subject to such an anomaly, and yet none has ever been witnessed. This would evidently conclude that it is not increased resistance causing the spike..........Like I said I'm having a hard time wrapping my head around a logical explanation for such an event to take place.

 

[marshman]

I talked to Jim Ristow at RSI years ago about secondary spikes, it has shown up on traces (not mine) and yes its very hard to
get ones head around it.
Getting a little derailed here but there is also powder bridging from extruded powder which causes spikes... in theory at least.
And the only way to see it so far is with a strain gauge on the chamber.

I can understand the bridging effect, that's whats happening today when hoards of shoppers try to get into stores all at once..

 

[nowarningshot]

This entire secondary pressure spike is graduate school level to my grade 10, when it comes to loading. What i would like to know is two things...and this gets back to the OP's question.

Firstly the 30-06 family has some small graduations in bore. So with the common maximum projectiles of 120 and 160gr between the 25-06 and 270, what does one gain in a 25-06 in pushing even heavier projectile that is not easily seen by using say a 270 with 130-140 gr pills?

Next, what are peoples source for these large 257 projectiles, the largest i can find are 120's. Who makes them, and where are they for sale?

There are lots of other 25 cals, but the most common are the 257 Bob, 25-06, and 257 Roy. Lots of wildcats but the latter two, from above are the most common that would benefit from large projectile....like i said ....i am not to the level of experimenting with wildcats.

 

[Pathfinder]

As Above, Matrix bullets, marshman is actually the guy.

 

[Grey_Wolf]

As Above, Matrix bullets, marshman is actually the guy.

I tried to buy some bullets last fall from him - .257 and .264 I think. Anyway ordered online, sent Visa for payment and.... he sent me a message - none in stock. Sent my money back. Sent an email back wondering about when or back-order or what. No, none, don't know. No indication on the web site that there were none in stock. I have a friend that called him and he wasn't too interested in giving any information on when stock might be available. Oh well. I like to support business at home (Canadian) but not if they aren't interested in my business.

 

[K-C]

Maybe Barnes Bullets might be able to help you?

Fred Barnes developed a cartridge in the late 1940s that used a 200 grain 6.5 bullet. It was called the 6.5 QT (quick twist) and was based on the .250 Ackley Magnum. This cartridge required a 5 to 6 inch twist barrel...