22-250 COUNTACH

[Dale SH]

Because if you dont you may be the one who ends up with swollen lips

[jdpretorius]

Because if you dont you may be the one who ends up with swollen lips

Sent from my SM-G570F using Tapatalk

[Messor]

@DD

I believe the struggle made you vulnerable to influence on the bad side of the force.

This Dale guy knows what he is talking about, either the rifle shoots safe loads or it doesn't.
If it doesn't then the science behind it becomes very interesting, as most rifles groups best at max or just beyond.
Every tool have a purpose, I believe this tool did not live up to your expectations.

[Hercules Louw]

DD, hoe lyk jou doppe waarmee jy die 69gr Lapuas geskiet het? Is daar enige sigbare tekens van druk soos ejector merke op die doppe se gesigte, moeilik om die doppe uit die kamer te trek, gevuurde doppe wat nie weer wil kamer nie, slagdoppies wat krater of slagdoppie gate wat gerek het? Teen die drukvlakke wat die QL berekeninge toon moet daar ook ernstige sigbare druk tekens wees, of anders is die QL berekende drukvlakke nie korrek nie.

[Diesel Dog]

@DD
I believe the struggle made you vulnerable to influence on the bad side of the force.
This Dale guy knows what he is talking about, either the rifle shoots safe loads or it doesn't.
If it doesn't then the science behind it becomes very interesting, as most rifles groups best at max or just beyond.
Every tool have a purpose, I believe this tool did not live up to your expectations.

I believe the struggle made you vulnerable to influence on the bad side of the force.

Yes I am contemplating the use of brute force!

This Dale guy knows what he is talking about

About reloading you are correct , about long term monogamous relationships I wil rather trust my own judgement

If it doesn't then the science behind it becomes very interesting, as most rifles groups best at max or just beyond.

I have a theory that is supported by numerous targets with different types of bullets , the results of which suggest that the shorter and harder the bullet and slower the load the more consistent the groups .On the contrary the longer and softer the bullet and faster the load the more erratic the groups are.

My conclusions are that due to the design of the rifling it is kneading the bullet like dough and not getting sufficient purchase on the entire mass of the bullet to impart the spin required to stabilize the bullet at the speed that this caliber was designed for.

By jamming the bullet into the lands wil prevent any axial acceleration to take place before radial acceleration of the bullet and i surmise the increased pressure wil aid the slump effect of the bullet to better fill the bore thereby gaining purchase on the bullet to impart the design spin.

If I am barking up the wrong tree please enlighten me.

DD

[Diesel Dog]

DD, hoe lyk jou doppe waarmee jy die 69gr Lapuas geskiet het? Is daar enige sigbare tekens van druk soos ejector merke op die doppe se gesigte, moeilik om die doppe uit die kamer te trek, gevuurde doppe wat nie weer wil kamer nie, slagdoppies wat krater of slagdoppie gate wat gerek het? Teen die drukvlakke wat die QL berekeninge toon moet daar ook ernstige sigbare druk tekens wees, of anders is die QL berekende drukvlakke nie korrek nie.

Primers het kraters , as jy in goeie lig kyk dan is daar ligte ejector merke. maar niks meer as wat ek sou verwag van n stywe lading.

[Dale SH]

As a comparison.
Here is Nosler's load data for a 69 grain bulet with N540
From a 24 inch barrel they achieve 3283 fps, which is predicted to be a 60 000 psi load.
From a 28 inch barrel this would equate roughly to +-3390 fps
So to achieve DD's 3525 fps from a 28 inch barrel would equate to +- 70 000 to 72000psi
Roughly in line with my original calcualtion.

[Pappabeer]

Ek verstaan nou nie QL nie, maar tref hy onderskeid tussen MRR en konvensionele rifling tydens julle drukberekeninge?

[Diesel Dog]

As a comparison.
Here is Nosler's load data for a 69 grain bulet with N540
From a 24 inch barrel they achieve 3283 fps, which is predicted to be a 60 000 psi load.
From a 28 inch barrel this would equate roughly to +-3390 fps
So to achieve DD's 3525 fps from a 28 inch barrel would equate to +- 70 000 to 72000psi
Roughly in line with my original calcualtion.

I just shot three of the same loads with 1 mm reduced tpl and speed was 3465,3501, 3513fps

DD

[Diesel Dog]

Ek verstaan nou nie QL nie, maar tref hy onderskeid tussen MRR en konvensionele rifling tydens julle drukberekeninge?

Bedoel jy soos as ek my flight medical doen en ek blaas deur 'n strooitjie dan kan ek lekker druk opbou maar as hulle daai kreepy krauly pyp gee ,niks maak nie no pressure.

DD

[Dale SH]

One thing is becoming quite clear here DD
This rifling design does not like the difference between a cold and hot barrel as can be witnessed by the increase in MV from shot 1 to shot 2
My recommendation remains.
Shoot a 32.5 grain load ( with the reduced COL which I assume is now +- 63.60mm) and if your burn rate does not decrease too much then MV should be in the region of 3320 - 3345 fps, and this should bring you close to an accurate node within safe pressure.

[OosKaapJagter]

Ek kyk as 'n buitestaander na hierdie sage.

Dit lyk my die eienaar is moedeloos en keelvol. Die kenners is deurmekaar.

As 'n gewone jagter wat nie sommer oor 300m skiet nie, is Quickload vir my 'n toe boek. Ek het nog altyd goed daarsonder reggekom. Ek gaan egter twee dom vrae vra.

Is Quickload ontwerp om data te verskaf op konvensionele lope met standaard groewe?

Gaan die "multi radial rifling" van Sabatti nie dalk minder wrywing met gepaardgaande hoër trompsnelhede toelaat, sonder verhoogde druk nie? https://www.thefirearmblog.com/blog/201 ... l-rifling/


Indien dit my geweer was sou ek oorweeg om te kyk watter spoed word verkry met fabrieksammunisie uit hierdie geweer en dit dan te vergelyk met die spoed uit 'n konvensionele loop. Dit kan dalk 'n goeie riglyn vir kalibrasie verskaf.

As ek heeltemal van die wa af is, verskoon maar die onkunde.

[Dale SH]

@ papabeer and ooskaapjagter

I can not give you a definitive answer regarding the pressure calculations between a conventional barrel and MRR barrel. I will have to do some research on this subject.
However there are two different factors at play here.
1. Is the load over presssure ? I believe so as DD is experiencing cratered primers and light extractor marks on the case head.
2. Accuracy. Regardless of the pressure his rifle should not be shooting groups of between 4 and 7 MOA.
An off the shelf rifle with factory ammo should be quite capable of at least 2MOA max.

DD has confirmed that the rifle is sufficiently free floated and that it is not touching the stock at any point.
His groups at low pressure are somewhat acceptable but the moment the pressure increases the rifle throws the bullets around like a shot gun.
I'm leaning towards the notion that this barrel has excess whip/flex/walk (alla an old 303 when shooting strings)
Whether this is due to poor matallurgy or the this specific rifling I can not say.

I too would like to see what type of grouping this rifle achieves with some 55 grain good quality factory ammo.

[Diesel Dog]

One thing is becoming quite clear here DD
This rifling design does not like the difference between a cold and hot barrel as can be witnessed by the increase in MV from shot 1 to shot 2
My recommendation remains.
Shoot a 32.5 grain load ( with the reduced COL which I assume is now +- 63.60mm) and if your burn rate does not decrease too much then MV should be in the region of 3320 - 3345 fps, and this should bring you close to an accurate node within safe pressure.

This difference in velocity has given me the runs from the start.

Correct me if I am wrong but once calibrated with the specific components ,i.e.barrel ,bullet, powder ,case ect. The friction generated by the system is considered by the program to derive a suitable load .

DD

[Dale SH]

Correct.

In your case the calibration factor (the BRF) is showing as substantially higher than the norm which leads me too believe that this MRR rifling may in fact be generating considerably higher MV for a given charge weight versus a "conventional" barrel

[Diesel Dog]

I just shot 32.5 gr 63.6mm tpl and new battery in magneto speed
1 3244fps
2 3306fps

DD

[Dale SH]

F**** it.
There's that MV spread again.

I am going to use the 3306 fps as a calibration load and say shoot 32.9 grains for 3336 fps to achieve the accurate node.
56000 psi.

If your grouping is still shit then I will supply the vaseline for you to give to the supplier.

Any cratered primers or extractor marks on the abovementioned two cases ?

[Diesel Dog]

F**** it.
There's that MV spread again.

I am going to use the 3306 fps as a calibration load and say shoot 32.9 grains for 3336 fps to achieve the accurate node.
56000 psi.

If your grouping is still shit then I will supply the vaseline for you to give to the supplier.

Any cratered primers or extractor marks on the abovementioned two cases ?

NO primers and cases are show quality.

DD

[Diesel Dog]

When the rifle was returned the second time I sent them 80x 75gr amax and eldm AS THESE WHERE my bullets of choice, but they chose to develop a load for a 69gr scenar bullet .I wonder what was the logic in that?

DD

[Dale SH]

Because the Sabatti agents are also the importers of Lapua products.
I also note that the 22-250 does not appear in the Sabatti catalogue anymore on their website

[jdpretorius]

When the rifle was returned the second time I sent them 80x 75gr amax and eldm AS THESE WHERE my bullets of choice, but they chose to develop a load for a 69gr scenar bullet .I wonder what was the logic in that?

DD

DD my guess would be that they perhaps also couldn't get the amax and eldm's to group. Being a suspicious person by nature, I would think that they now know/knew that some thing is a miss

[Dale SH]

When the rifle was returned the second time I sent them 80x 75gr amax and eldm AS THESE WHERE my bullets of choice, but they chose to develop a load for a 69gr scenar bullet .I wonder what was the logic in that?

DD

DD my guess would be that they perhaps also couldn't get the amax and eldm's to group. Being a suspicious person by nature, I would think that they now know/knew that some thing is a miss

The sceptic in me thinks that this may be the same reason they removed the 22-250 from their product line up

[Messor]

Right, ek is nie 'n groot kenner op MRR nie, but here goes.

Soos ek verstaan, en hier is Sabatti se eie woorde :
Unlike conventional rifling, MRR doesn’t form the distinct grooves on the bullet jacket, but rather squeezes the bullet to fill the bore geometry

Nou hierdie sqeeze is waar al die nonsens begin, maar laat ek voor begin.
Jy kan nie 'n koeel vinnig skiet sonder om druk op te bou nie, so ek gee nie om of QL reg of verkeerd is nie, as die koeel die loop seel soos hulle noem gaan die ontbranding druk opbou en die koeel lanseer. In kort, dit sal nie 'n wonder loop wees wat skielik maak dat jy baie vinniger kan skiet nie, pressure = speed, niks minder en niks meer. So die heel eerste ding wat ek sal doen is versigtig wees, en alle QL berekeninge as waar aanskou.

Nou die druk storie, dit is my opinie dat die rede vir die swak groepering bloot die feit is dat die koeels vervorm(lees beskadig) word. Ek dink hulle kry seer deur 'n kombinasie van spoed en die spesifieke rifling, ek meen ek sien nie eens 'n 22-250 op hulle webwerf nie. Ons weet fabrikate soos Berger maak hulle target punte se mantels sterker as hul jagpunte, vir hierdie einste rede, om akuraatheid te behou as die koeel onder groot stres kom.

Stabilitiet word verhoog as jy 'n koeel vinniger skiet, die SG waarde word meer, nie minder nie. So as hierdie geweer skiet as die lading rustig is, dan neem ek aan die koeels stabiliseer. Maar nou die data wys die geweer se spoed gaan op soos hy warm word, dit dui weer op druk. Ek dink, die geweer kan nie sagte punte vinnig skiet nie, ek dink hy beskadig hulle. Ek kan verkeerd wees maar time will tell.

As die my geweer was, dan sou ek Berger target koeels gekoop het, en vergeet van QL, ek sou 'n ladder skiet van laag na hoog, die spoed meet en kyk waar ek akuraatheid begin verloor, menende waar ek die koeels begin seer maak, binne velige perke natuurlik.

[Diesel Dog]

The sceptic in me thinks that this may be the same reason they removed the 22-250 from their product line up

Unfortunately we are no privy to the facts and our assumptions are mere speculation.

The fact that the rifle in my possession does not conform to convention is what I am concerned about.

DD

[Diesel Dog]

Right, ek is nie 'n groot kenner op MRR nie, but here goes.

Soos ek verstaan, en hier is Sabatti se eie woorde :
Unlike conventional rifling, MRR doesn’t form the distinct grooves on the bullet jacket, but rather squeezes the bullet to fill the bore geometry

Nou hierdie sqeeze is waar al die nonsens begin, maar laat ek voor begin.
Jy kan nie 'n koeel vinnig skiet sonder om druk op te bou nie, so ek gee nie om of QL reg of verkeerd is nie, as die koeel die loop seel soos hulle noem gaan die ontbranding druk opbou en die koeel lanseer. In kort, dit sal nie 'n wonder loop wees wat skielik maak dat jy baie vinniger kan skiet nie, pressure = speed, niks minder en niks meer. So die heel eerste ding wat ek sal doen is versigtig wees, en alle QL berekeninge as waar aanskou.

Nou die druk storie, dit is my opinie dat die rede vir die swak groepering bloot die feit is dat die koeels vervorm(lees beskadig) word. Ek dink hulle kry seer deur 'n kombinasie van spoed en die spesifieke rifling, ek meen ek sien nie eens 'n 22-250 op hulle webwerf nie. Ons weet fabrikate soos Berger maak hulle target punte se mantels sterker as hul jagpunte, vir hierdie einste rede, om akuraatheid te behou as die koeel onder groot stres kom.

Stabilitiet word verhoog as jy 'n koeel vinniger skiet, die SG waarde word meer, nie minder nie. So as hierdie geweer skiet as die lading rustig is, dan neem ek aan die koeels stabiliseer. Maar nou die data wys die geweer se spoed gaan op soos hy warm word, dit dui weer op druk. Ek dink, die geweer kan nie sagte punte vinnig skiet nie, ek dink hy beskadig hulle. Ek kan verkeerd wees maar time will tell.

As die my geweer was, dan sou ek Berger target koeels gekoop het, en vergeet van QL, ek sou 'n ladder skiet van laag na hoog, die spoed meet en kyk waar ek akuraatheid begin verloor, menende waar ek die koeels begin seer maak, binne velige perke natuurlik.

Dit is min of meer soos ek dit het al waar ek verskil is dat ek nie nut het vir harde koeëls nie aangesien ek die geweer wil gebruik vir oes .

DD